Vulnerability · Published Sep 22, 2026 · Assigned by mitre
CVE-2026-88418
High 8.8
In plain English
A high-severity cross-site request forgery in the affected software. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 17% of all known vulnerabilities).
Official description
CMSimple 5.24 ships with CSRF protection disabled by default, which turns csrfProtection() into a no-op on every state-changing admin request, and it does not send the csrf_token hidden field in admin forms. Because administrator authentication is cookie-only and no CSRF token is enforced, an unauthenticated attacker can induce a logged-in administrator's browser to issue a forged content-save request with a text payload containing a scripting marker. The marker is stored verbatim into content/content.php; on every subsequent page view evaluate_cmsimple_scripting() (functions.php) executes the marker body with PHP eval() — for all visitors, including unauthenticated ones. This yields persistent remote code execution on the web server.
Affected products (as reported)
Weakness: CWE-352 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H