Difference between revisions of "Direct Static Code Injection"

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{{Template:Attack}}
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[[Category:OWASP ASDR Project]]
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==Description==
 
==Description==
  
==Consequence==
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A Direct Static Code Injection attack consists of 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.
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Upon a user request to the modified resource, the actions defined in it will be executed at server side in the context of web server process.
  
==Related Threats==
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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)| XSS]] (“Cross-site scripting” or “HTML injection”) where the code is executed on the client side.
  
==Related Vulnerabilities==
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==Risk Factors==
[[:Category:Lack of Input Validation]]
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TBD
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[[Category:FIXME|need content here]]
  
==Related Countermeasures==
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==Examples==
[[:Category:Input Validation]]
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[[Category:Attack]]
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===Example 1===
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This is a simple example of exploitation of a CGISCRIPT.NET csSearch 2.3 vulnerability, published on Bugtraq ID: 4368.
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By requesting the following URL to the server, it’s possible to execute commands defined on the ‘’’’setup’’’ variable.
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<br>
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csSearch.cgi?command=savesetup&setup=''PERL_CODE_HERE''
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For the classic example, the following command can be used to remove all files from “/” folder:
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csSearch.cgi?command=savesetup&setup=`rm%20-rf%20/`
  
[[Category:Injection Attack]]
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Note that the above command must be encoded in order to be accepted.
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===Example 2===
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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 the admin_iplog.php page to show user statistics. When an administrator browses this page, the previously injected code by a malicious request is executed.
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The following example stores a malicious PHP code that will deface the index.html page when an administrator browses admin_iplog.php.
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GET /board/index.php HTTP/1.0
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User-Agent: <? system( "echo \'hacked\' > ../index.html" ); ?>
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==Related [[Threat Agents]]==
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* [[Internal software developer]]
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==Related [[Attacks]]==
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* [[Server-Side Includes (SSI) Injection | Server Side Includes]]
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* [[ Direct Dynamic Code Evaluation ('Eval Injection')]]
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==Related [[Vulnerabilities]]==
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* [[:Category:Input Validation Vulnerability]]
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==Related [[Controls]]==
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* [[:Category:Input Validation]]
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==References==
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* http://www.seclab.tuwien.ac.at/advisories/TUVSA-0510-001.txt
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* http://marc.info/?l=bugtraq&m=105379741528925&w=2
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* http://archives.neohapsis.com/archives/bugtraq/2005-06/0002.html
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[[Category:Injection]]
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[[Category:Attack]]
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__NOTOC__

Latest revision as of 07:40, 7 April 2009

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



Last revision: 04/7/2009

Description

A Direct Static Code Injection attack consists of 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 in 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 the client side.

Risk Factors

TBD

Examples

Example 1

This is a simple example of exploitation of a 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 the ‘’’’setup’’’ variable.

csSearch.cgi?command=savesetup&setup=PERL_CODE_HERE


For the classic example, the following command can be used 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 the 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 the index.html page when an administrator browses admin_iplog.php.

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

Related Threat Agents

Related Attacks

Related Vulnerabilities

Related Controls

References