SRC-2016-0010 : ATutor LMS question_import Directory Traversal Remote Code Execution Vulnerability

CVE ID:

N/A</a>

CVSS Score:

7.5, (AV:N/AC:L/Au:N/C:P/I:P/A:P)

Affected Vendors:

ATutor

Affected Products:

ATutor 2.2.1 is confirmed, other versions may also be affected.

Vulnerability Details:

This vulnerability allows remote attackers to execute arbitrary code on vulnerable installations of ATutor. Authentication is required to exploit this vulnerability however authentication bypass vulnerabilities are known and remote registration is open by default.

The specific flaw exists in the ‘question_import.php’ script. An attacker can upload and extract a zip file containing a directory traversal attack. Files can be extracted into the applications web root by bypassing a poor blacklist sanity check from the preImportCallBack() function. An attacker can leverage this to upload and execute arbitrary php code.

Vendor Response:

ATutor has issued an update to correct this vulnerability. More details can be found at: https://github.com/atutor/ATutor/commit/d1517f1af8d94509394f05c04c387d76301a801b

Disclosure Timeline:

  • 2016-03-11 – Vulnerability reported to vendor
  • 2016-03-11 – CVE requested and rejected
  • 2016-03-12 – Vendor confirmed issue
  • 2016-03-19 – Vendor releases a patch
  • 2016-03-19 – Coordinated public release of advisory

Proof of Concept:

https://github.com/rapid7/metasploit-framework/blob/master/modules/exploits/linux/http/atutor_filemanager_traversal.rb

Credit:

This vulnerability was discovered by Steven Seeley of Source Incite