GitHub Advisoryadvisory · Packagist

GHSA-qv3x-mffx-9gw8 Concrete CMS is vulnerable to IDOR

MEDIUM Published 2026-05-22 Modified 2026-06-24 Official page ↗
Aliases
CVE-2026-8238
Ecosystem
Packagist
Packages
concrete5/concrete5
Severity
Moderate
CVSS 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
Weaknesses
CWE-862
Reviewed
2026-06-24

Affected packages

• Packagist concrete5/concrete5: < 9.5.1 → fixed in 9.5.1

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.

Related

Alias · CVE (1)

  • CVE-2026-8238 Concrete CMS 9.5.0 and below is vulnerable to IDOR. vulnerability

Weakness · CWE (1)

  • CWE-862 Missing Authorization weakness

References