Medium severity5.3NVD Advisory· Published May 21, 2026· Updated Jul 23, 2026
CVE-2026-8237
CVE-2026-8237
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. 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 Eldudareeno for reporting.
AI Insight
LLM-synthesized narrative grounded in this CVE's description and references.
Affected packages
Versions sourced from the GitHub Security Advisory.
| Package | Affected versions | Patched versions |
|---|---|---|
concrete5/concrete5Packagist | < 9.5.1 | 9.5.1 |
Affected products
3- Range: <=9.5.0
Patches
Vulnerability mechanics
References
3- github.com/advisories/GHSA-xpgc-7vc2-8725ghsaADVISORY
- nvd.nist.gov/vuln/detail/CVE-2026-8237ghsaADVISORY
- documentation.concretecms.org/9-x/developers/introduction/version-history/951-release-notesnvdRelease NotesWEB
News mentions
1- Concrete CMS: 25 CVEs Disclosed Together, 12 High-Severity CSRF Bugs Lead the BatchVypr Intelligence · May 22, 2026