CVE-2026-81907 Details

Concrete CMS 9.5.2 and below is vulnerable to Cross-Site Request Forgery (CSRF) in the Express "Clear Entries" function (POST /index.php/dashboard/system/express/entities/delete_entries) because the controller records but does not enforce a failed CSRF token check, allowing the destructive operation to proceed when the token is missing or invalid. A remote unauthenticated attacker can force an authenticated administrator who visits an attacker-controlled page to permanently delete all entries belonging to an attacker-selected Express entity on a web application to which the administrator is currently authenticated. Because the default Contact Express object ships with a fixed entity UUID, the target identifier can be obtained without dashboard access. The Concrete CMS security team gave this vulnerability a CVSS v4.0 score of 6.1 with vector CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N. Thanks Pratik Zanjurne for reporting.