Vulnerability Description
Concrete CMS 9.5.0 and below is vulnerable to IDOR. The '/ccm/frontend/conversations/message_page' endpoint returns the full content of any conversation message. An unauthenticated attacker can enumerate all conversation messages, including messages from restricted pages, member-only areas, and the moderation queue. File attachments with download URLs are also exposed. The Concrete CMS security team gave this vulnerability a CVSS v.4.0 score of 6.3 with Vector CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N. Thanks Tristan Madani for reporting.
Related Weaknesses (CWE)
References
FAQ
What is CVE-2026-8238?
CVE-2026-8238 is a documented vulnerability. Concrete CMS 9.5.0 and below is vulnerable to IDOR. The '/ccm/frontend/conversations/message_page' endpoint returns the full content of any conversation message. An unauthenticated attacker can enumer...
How severe is CVE-2026-8238?
CVSS scoring is not yet available for CVE-2026-8238. Check NVD for updates.
Is there a patch for CVE-2026-8238?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.