Privilege escalation in Thorsten Phpmyfaq
CVE-2026-66399
phpMyFAQ before 4.1.6 contains a privilege escalation vulnerability in GroupController::updateMembers() that allows administrators with only group-management permissions to join privileged groups without verification of required rights. Attackers can add themselves to pre-existing groups holding user-management rights and immediately inherit those permissions to modify or delete user accounts.
Vulnerability class: Privilege Escalation
EPSS: 0.002 (13.9th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N.
Affected products
- Thorsten Phpmyfaq — versions 0, 4.1.6
Weakness classification (CWE)
References
- GitHub Security Advisory (GHSA-28cc-v39j-vr95) (vendor-advisory)
- VulnCheck Advisory: phpMyFAQ before 4.1.6 Privilege Escalation via Group Membership (third-party-advisory)
Frequently asked questions
- What is CVE-2026-66399?
- CVE-2026-66399 is a medium-severity vulnerability in Thorsten Phpmyfaq, classified under Improper Privilege Management. CVSS score: 6.5/10. Published 2026-07-27.
- How severe is CVE-2026-66399?
- Medium severity. CVSS v3 base score is 6.5 out of 10.