CVE-2026-8237
Published:May 21, 2026
Updated:June 11, 2026
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.
Affected Packages
concrete5/concrete5 (PHP):
Affected version(s) >=dev-allow-install-php-8.2 <9.5.1Fix Suggestion:
Update to version 9.5.1Related Resources (1)
Do you need more information?
Contact UsCVSS v4
Base Score:
6.3
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
PRESENT
Privileges Required
NONE
User Interaction
NONE
Vulnerable System Confidentiality
LOW
Vulnerable System Integrity
NONE
Vulnerable System Availability
NONE
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
5.3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
LOW
Integrity
NONE
Availability
NONE
Weakness Type (CWE)
Missing Authorization
EPSS
Base Score:
0.05