PublicCVE

CVE-2026-43920

MEDIUM6.9JSON exportCreate alert

Description

FOSSBilling is a free, open-source billing and client management system. In versions 0.5.4 through 0.7.2, the /run-patcher maintenance endpoint in FOSSBilling was accessible without authentication, which allowed unauthenticated remote users to trigger update patch routines that modify configuration files, execute database schema changes, perform filesystem mutations, and clear caches. The /run-patcher endpoint executes privileged maintenance operations - configuration migrations, database patch execution (including ALTER TABLE, DROP TABLE, UPDATE statements), filesystem deletions and renames, and cache clearing - without requiring administrator authentication, CSRF validation, or CLI context. An unauthenticated remote attacker can trigger these operations by sending a simple HTTP GET request to /run-patcher, which can be abused for denial-of-service attacks. Certain patches (e.g., batch token regeneration for all admin and client accounts in patch 53, and session invalidation) are disruptive even when re-executed against an already-patched instance. Repeated or concurrent requests may also cause inconsistent database state. This issue has been fixed in version 0.8.0.

CVSS breakdown

CVSS 4.0
Attack Vector
Network
Attack Complexity
Low
Attack Requirements
None
Privileges Required
None
User Interaction
None
Confidentiality (Vulnerable System)
None
Integrity (Vulnerable System)
Low
Availability (Vulnerable System)
Low
Confidentiality (Subsequent System)
None
Integrity (Subsequent System)
None
Availability (Subsequent System)
None

Affected products