Difference between revisions of "Direct Static Code Injection"

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{{Template:Attack}}
 
{{Template:Attack}}
 
  
 
==Description==
 
==Description==
 
 
Direct Static Code Injection attack consists on injecting code directly onto the resource used by application while processing a user request. This is normally performed by tampering libraries and template files which are created based on user input without proper data sanitization.  
 
Direct Static Code Injection attack consists on injecting code directly onto the resource used by application while processing a user request. This is normally performed by tampering libraries and template files which are created based on user input without proper data sanitization.  
 
Upon a user request to the modified resource, the actions defined on it will be executed at server side in the context of web server process.
 
Upon a user request to the modified resource, the actions defined on it will be executed at server side in the context of web server process.
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[[Server-Side Includes (SSI) Injection | Server Side Includes]] is considered a type of direct static code injection. It should not be confused with other types of code injection, like [[Cross Site Scripting | XSS]] (“Cross Site Scripting” or “HTML injection”) where the code is executed on client side.   
 
[[Server-Side Includes (SSI) Injection | Server Side Includes]] is considered a type of direct static code injection. It should not be confused with other types of code injection, like [[Cross Site Scripting | XSS]] (“Cross Site Scripting” or “HTML injection”) where the code is executed on client side.   
  
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==Severity==
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High
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==Likelihood of exploitation==
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Medium to Low
  
 
==Examples ==
 
==Examples ==
  
 
===Example 1===
 
===Example 1===
 
 
This is a simple example of exploitation of CGISCRIPT.NET csSearch 2.3 vulnerability, published on Bugtraq ID: 4368.
 
This is a simple example of exploitation of CGISCRIPT.NET csSearch 2.3 vulnerability, published on Bugtraq ID: 4368.
 
By requesting the following URL to the server, it’s possible to execute commands defined on ‘’’’setup’’’ variable.
 
By requesting the following URL to the server, it’s possible to execute commands defined on ‘’’’setup’’’ variable.
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Note that the above command must be encoded in order to be accepted.
 
Note that the above command must be encoded in order to be accepted.
 
  
 
===Example 2===
 
===Example 2===
 
 
This example exploits a vulnerability on Ultimate PHP Board (UPB) 1.9 (CVE-2003-0395), which allows an attacker to execute random php code. This happens because some user variables, like IP address and User-Agent, are stored in a file that is used by admin_iplog.php page to show user statistics. When an administrator browses this page, the previously injected code by a malicious request is executed.  
 
This example exploits a vulnerability on Ultimate PHP Board (UPB) 1.9 (CVE-2003-0395), which allows an attacker to execute random php code. This happens because some user variables, like IP address and User-Agent, are stored in a file that is used by admin_iplog.php page to show user statistics. When an administrator browses this page, the previously injected code by a malicious request is executed.  
 
The following example stores a malicious PHP code that will deface index.html page when administrator browses admin_iplog.php.
 
The following example stores a malicious PHP code that will deface index.html page when administrator browses admin_iplog.php.
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  User-Agent: <? system( "echo \'hacked\' > ../index.html" ); ?>
 
  User-Agent: <? system( "echo \'hacked\' > ../index.html" ); ?>
  
 
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==External references==
==References==
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http://www.seclab.tuwien.ac.at/advisories/TUVSA-0510-001.txt
 
http://www.seclab.tuwien.ac.at/advisories/TUVSA-0510-001.txt
 
 
http://cve.mitre.org/docs/plover/SECTION.9.21.html#CODE.STAT
 
http://cve.mitre.org/docs/plover/SECTION.9.21.html#CODE.STAT
 
 
http://marc.info/?l=bugtraq&m=105379741528925&w=2
 
http://marc.info/?l=bugtraq&m=105379741528925&w=2
 
 
http://archives.neohapsis.com/archives/bugtraq/2005-06/0002.html
 
http://archives.neohapsis.com/archives/bugtraq/2005-06/0002.html
 
  
 
==Related Threats==
 
==Related Threats==
{{Template:Stub}}
 
 
 
[[:Category:Command Execution]]
 
[[:Category:Command Execution]]
 
  
 
==Related Attacks==
 
==Related Attacks==
 
 
*[[Server-Side Includes (SSI) Injection | Server Side Includes]]
 
*[[Server-Side Includes (SSI) Injection | Server Side Includes]]
 
*[[ Direct Dynamic Code Evaluation ('Eval Injection')]]
 
*[[ Direct Dynamic Code Evaluation ('Eval Injection')]]
 
  
 
==Related Vulnerabilities==
 
==Related Vulnerabilities==
 
 
[[:Category:Input Validation Vulnerability]]
 
[[:Category:Input Validation Vulnerability]]
  
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[[:Category:Input Validation]]
 
[[:Category:Input Validation]]
  
 
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[[Category:Injection]]
==Categories==
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[[Category:Attack]]
 
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[[:Category:Injection Attack]]
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[[:Category: Input Validation]]
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[[Category: Resource Manipulation]]
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Revision as of 11:30, 5 November 2007

This is an Attack. To view all attacks, please see the Attack Category page.


Description

Direct Static Code Injection attack consists on injecting code directly onto the resource used by application while processing a user request. This is normally performed by tampering libraries and template files which are created based on user input without proper data sanitization. Upon a user request to the modified resource, the actions defined on it will be executed at server side in the context of web server process.

Server Side Includes is considered a type of direct static code injection. It should not be confused with other types of code injection, like XSS (“Cross Site Scripting” or “HTML injection”) where the code is executed on client side.

Severity

High

Likelihood of exploitation

Medium to Low

Examples

Example 1

This is a simple example of exploitation of CGISCRIPT.NET csSearch 2.3 vulnerability, published on Bugtraq ID: 4368. By requesting the following URL to the server, it’s possible to execute commands defined on ‘’’’setup’’’ variable.

csSearch.cgi?command=savesetup&setup=PERL_CODE_HERE


For the classical example, it can be used the following command to remove all files from “/” folder: csSearch.cgi?command=savesetup&setup=`rm%20-rf%20/`

Note that the above command must be encoded in order to be accepted.

Example 2

This example exploits a vulnerability on Ultimate PHP Board (UPB) 1.9 (CVE-2003-0395), which allows an attacker to execute random php code. This happens because some user variables, like IP address and User-Agent, are stored in a file that is used by admin_iplog.php page to show user statistics. When an administrator browses this page, the previously injected code by a malicious request is executed. The following example stores a malicious PHP code that will deface index.html page when administrator browses admin_iplog.php.

GET /board/index.php HTTP/1.0
User-Agent: <? system( "echo \'hacked\' > ../index.html" ); ?>

External references

http://www.seclab.tuwien.ac.at/advisories/TUVSA-0510-001.txt http://cve.mitre.org/docs/plover/SECTION.9.21.html#CODE.STAT http://marc.info/?l=bugtraq&m=105379741528925&w=2 http://archives.neohapsis.com/archives/bugtraq/2005-06/0002.html

Related Threats

Category:Command Execution

Related Attacks

Related Vulnerabilities

Category:Input Validation Vulnerability


Related Countermeasures

Category:Input Validation