CVE-2026-8237 Details.
Concrete CMS <= 9.5.0 - Unauthenticated Conversation Message Disclosure (IDOR)
Atlas does not check this one. Needs requests that change data.
To test for this one, the check would have to send requests that could change data on the site. Atlas only ever reads public pages, so it does not run this check.
About CVE-2026-8237. What It Means.
Concrete CMS <= 9.5.0 contains an IDOR caused by insufficient access control in /ccm/frontend/conversations/message_detail endpoint, letting unauthenticated attackers enumerate conversation messages and attachments.
Affected Product. What Is Hit.
- Vendor
- concretecms
- Product
- Concretecms Concrete CMS
More CVEs In Concretecms Concrete CMS.
FAQ
Common Questions.
Concrete CMS <= 9.5.0 - Unauthenticated Conversation Message Disclosure (IDOR). Concrete CMS <= 9.5.0 contains an IDOR caused by insufficient access control in /ccm/frontend/conversations/message_detail endpoint, letting unauthenticated attackers enumerate conversation messages and attachments.
No. To test for this one, the check would have to send requests that could change data on the site. Atlas only ever reads public pages, so it does not run this check. The facts about CVE-2026-8237 are on this page, and you can request a demo to see how Brandefense watches your whole external attack surface.
CVE-2026-8237 is not on the CISA Known Exploited Vulnerabilities list at the time of writing, but it is still worth fixing.
Update Concretecms Concrete CMS to the latest version from the vendor, or follow the vendor's advice to switch off the affected feature. Vendor links are listed on this page when they are known.
This page lists the public facts about CVE-2026-8237. Atlas does not run a check for it, so nothing here says whether a particular site is affected.