Security Advisory - Curesec Research Team 1. Introduction Affected Product: ClipperCMS 1.3.0 Fixed in: not fixed Fixed Version Link: n/a Vendor Website: http://www.clippercms.com/ Vulnerability Type: Code Execution Remote Exploitable: Yes Reported to vendor: 10/02/2015 Disclosed to public: 11/13/2015 Release mode: Full Disclosure CVE: n/a Credits Tim Coen of Curesec GmbH 2. Vulnerability Description CVSS High 9.0 AV:N/AC:L/Au:S/C:C/I:C/A:C Description The file upload uses a whitelist to only allow non-dangerous file extensions. However, it does allow the upload of .htaccess files, which means that an attacker can upload files with any extension and still gain code execution. An account is required to upload files. The role the account is in needs the right to upload files. By default, the lowest user role - Editor - has this right. 3. Proof of Concept The file upload can be found here: http://localhost/ClipperCMS-clipper_1.3.0/manager/index.php?a=31 To gain code execution, upload a .htaccess file with the content: AddType application/x-httpd-php .png Now, any uploaded file containing PHP code with the extension .png will be executed. 3. Solution This issue has not been fixed by the vendor. 4. Report Timeline 10/02/2015 Informed Vendor about Issue (no reply) 10/21/2015 Reminded Vendor of Disclosure Date (no reply) 11/13/2015 Disclosed to public Blog Reference: http://blog.curesec.com/article/blog/ClipperCMS-130-Code-Execution-95.html