Privilege escalation via unrestricted group membership assignment
Published Jul 27, 2026 · Updated Jul 27, 2026
Privilege escalation in phpMyFAQ before 4.1.6 allows remote authenticated users with group-management rights to gain user-management rights. GroupController::updateMembers() checks only GROUP_EDIT before replacing a group's membership and never verifies that the acting administrator holds every permission granted by that group. Exploitation requires a pre-existing group with stronger rights; successful membership changes permit account modification or deletion.
Summary
What happened
Privilege escalation in phpMyFAQ before 4.1.6 allows remote authenticated users with group-management rights to gain user-management rights. GroupController::updateMembers() checks only GROUP_EDIT before replacing a group's membership and never verifies that the acting administrator holds every permission granted by that group. Exploitation requires a pre-existing group with stronger rights; successful membership changes permit account modification or deletion.
The record
- CVE
- CVE-2026-66399
- Published
- Jul 27, 2026
- Updated
- Jul 27, 2026
- Vendor
- Thorsten Rinne
- Product
- phpMyFAQ
- Classifications
- CWE-862, CWE-269, T1098
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Jul 27, 2026CVE publishedPublication date reported by the CVE source.
- Jul 27, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=0 <4.1.6
What conditions does exploitation require?
What is affected?
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
- GHSA-28cc-v39j-vr95 authenticated group-membership PoCproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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