CVE-2026-7882
MediumCVSS 4.3Exploitation Probability (EPSS)
Low risk2th percentile - higher than 2% of all known CVEs
Summary
Concrete CMS version 9.5.0 and below is vulnerable to unauthorized file deletion due to an inverted CSRF token check in the DeleteFile controller. The CSRF token is rejected when valid and accepted when invalid, enabling CSRF attacks against users with permission to edit conversation messages.
Risk Assessment
The risk involves the possibility of an attacker deleting files without the victim's consent, potentially leading to data loss and system integrity compromise.
Recommendation
It is recommended to immediately upgrade to a version above 9.5.0, which includes a fix for proper CSRF token validation.
Original NVD description (English source)
Concrete CMS 9.5.0 and below is vulnerable to unauthorized file deletion due to an Inverted CSRF token check in the DeleteFile controller. The code throws an error when the token IS valid and proceeds with file deletion when the token is invalid or missing. This effectively disables CSRF protection for the file deletion endpoint, allowing cross-site request forgery attacks against users who have permission to edit conversation messages. The Concrete CMS security team gave this vulnerability a CVSS v.4.0 score of 2.3 with a vector of CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N. Thanks Tristan Mandani for reporting.