CVE-2026-8237
Concrete CMS is vulnerable to IDOR
EPSS 0.20%
Description
Concrete CMS 9.5.0 and below is vulnerable to IDOR. The `/ccm/frontend/conversations/message_detail` 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.
How to fix CVE-2026-8237
To remediate CVE-2026-8237, upgrade the affected package to a fixed version below.
- Packagist/concrete5/concrete5—upgrade to 9.5.1 or later
Is CVE-2026-8237 being exploited?
Low — EPSS is 0.2%, meaning exploitation activity has not been observed at scale.
Affected packages (1)
- from 0, < 9.5.1
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 4.0 | — | 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 |