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.
Metrics
Affected Vendors & Products
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History
Fri, 22 May 2026 13:30:00 +0000
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Thu, 21 May 2026 22:45:00 +0000
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Thu, 21 May 2026 21:45:00 +0000
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| 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. | |
| Title | Concrete CMS 9.5.0 and below is vulnerable to IDOR in '/ccm/frontend/conversations/message_page' allowing unauthenticated read of any conversation message | |
| Weaknesses | CWE-862 | |
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| Metrics |
cvssV4_0
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Status: PUBLISHED
Assigner: ConcreteCMS
Published:
Updated: 2026-05-22T12:30:59.976Z
Reserved: 2026-05-09T15:48:41.906Z
Link: CVE-2026-8238
Updated: 2026-05-22T12:30:56.075Z
Status : Received
Published: 2026-05-21T22:16:49.893
Modified: 2026-05-21T22:16:49.893
Link: CVE-2026-8238
No data.
OpenCVE Enrichment
Updated: 2026-05-21T22:30:20Z