Executive brief
e107 is a content management system (CMS) used to build and manage websites. A security flaw in the system's comment moderation tool allows attackers to trick logged-in administrators or moderators into performing unintended actions. By convincing a site manager to visit a malicious link, an attacker can silently delete legitimate comments or approve malicious ones without the manager's knowledge or consent.
Technical details
A Cross-Site Request Forgery (CSRF) vulnerability exists in e107 CMS due to improper token validation in the session_handler::check() function. The root cause is that the system only validates a CSRF token if one is present in the request; if the token is omitted entirely, the validation check is bypassed. An attacker can exploit this by hosting a malicious webpage that sends forged POST requests to the comment.php moderation endpoints (delete and approve modes). If an authenticated administrator or moderator visits the attacker's site, the forged requests will execute in their session context. This allows for the unauthorized modification of comment states in the database. The issue is fixed in version 2.3.5 by enforcing token presence for state-mutating requests.
Affected products
- e107inc e107 < 2.3.5
Timeline
- 2026-05-13: other: Vulnerability discovered by researcher
- 2026-05-18: advisory: GitHub security advisory published
- 2026-05-26: disclosed: CVE published to NVD
- 2026-05-26: patched: Fix released in version 2.3.5