CVE-2021-22967: Concretecms Concrete CMS

High severity, CVSS 7.5. EPSS: 1.1% chance of exploitation in the next 30 days.

In Concrete CMS (formerly concrete 5) below 8.5.7, IDOR Allows Unauthenticated User to Access Restricted Files If Allowed to Add Message to a Conversation.To remediate this, a check was added to verify a user has permissions to view files before attaching the files to a message in "add / edit message”.Concrete CMS security team gave this a CVSS v3.1 score of 4.3 AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:NCredit for discovery Adrian H

Affected products

• Concretecms Concrete CMS: before 8.5.7 (fixed in 8.5.7)

Published 2021-11-19. Last modified 2026-06-17.