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.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.2 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required HIGH

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/thorsten/phpMyFAQ/security/advisories/GHSA-28cc-v39j-vr95
https://www.vulncheck.com/advisories/phpmyfaq-before-privilege-escalation-via-group-membership
https://github.com/thorsten/phpMyFAQ/security/advisories/GHSA-28cc-v39j-vr95

Configurations

No configuration.

History

No history.

Information

Published : 2026-07-27 16:18

Updated : 2026-07-28 16:20

NVD link : CVE-2026-66399

Mitre link : CVE-2026-66399

CVE.ORG link : CVE-2026-66399

JSON object : View

Products Affected

No product.

CWE

CWE-269

Improper Privilege Management

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