Admidio is an open-source user management solution. Versions 5.0.6 and below contain a critical unrestricted file upload vulnerability in the Documents & Files module. Due to a design flaw in how CSRF token validation and file extension verification interact within UploadHandlerFile.php, an authenticated user with upload permissions can bypass file extension restrictions by intentionally submitting an invalid CSRF token.
This allows the upload of arbitrary file types, including PHP scripts, which may lead to Remote Code Execution on the server, resulting in full server compromise, data exfiltration, and lateral movement. This issue has been fixed in version 5.0.7.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Privileges Required
Low
Basic privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
High
Complete data leak
Integrity
High
Complete data modification
Availability
High
Complete denial of service
CVSS Vector v3.1