Emlog is an open source website building system. emlog v2.6.1 and earlier exposes a REST API endpoint (/index.php?rest-api=upload) for media file uploads. The endpoint fails to implement proper validation of file types, extensions, and content, allowing authenticated attackers (with a valid API key or admin session cookie) to upload arbitrary files (including malicious PHP scripts) to the server. An attacker can obtain the API key either by gaining administrator access to enable the REST API setting, or via information disclosure vulnerabilities in the application.
Once uploaded, the malicious PHP file can be executed to gain remote code execution (RCE) on the target server, leading to full server compromise.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Attack Requirements
None
No additional conditions
Privileges Required
None
No 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 v4.0
Weakness Type (CWE)
Vulnerable Products
emlog:emlog