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

28 Jul 2026, 16:20

Type	Values Removed	Values Added
References	~~() https://github.com/thorsten/phpMyFAQ/security/advisories/GHSA-28cc-v39j-vr95 -~~	() https://github.com/thorsten/phpMyFAQ/security/advisories/GHSA-28cc-v39j-vr95 -

27 Jul 2026, 16:18

Type	Values Removed	Values Added
New CVE

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

{"id": "CVE-2026-66399", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-66399", "role": "CISA Coordinator", "options": [{"exploitation": "poc"}, {"automatable": "no"}, {"technicalImpact": "total"}], "version": "2.0.3", "timestamp": "2026-07-28T14:51:28.427364Z"}}], "cvssMetricV31": [{"type": "Secondary", "source": "disclosure@vulncheck.com", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 6.5, "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "NONE", "privilegesRequired": "HIGH", "confidentialityImpact": "HIGH"}, "impactScore": 5.2, "exploitabilityScore": 1.2}], "cvssMetricV40": [{"type": "Secondary", "source": "disclosure@vulncheck.com", "cvssData": {"Safety": "NOT_DEFINED", "version": "4.0", "Recovery": "NOT_DEFINED", "baseScore": 8.5, "Automatable": "NOT_DEFINED", "attackVector": "NETWORK", "baseSeverity": "HIGH", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X", "exploitMaturity": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED", "userInteraction": "NONE", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "HIGH", "subIntegrityImpact": "NONE", "vulnIntegrityImpact": "HIGH", "integrityRequirement": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "vulnAvailabilityImpact": "NONE", "availabilityRequirement": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "subConfidentialityImpact": "NONE", "vulnConfidentialityImpact": "HIGH", "confidentialityRequirement": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED"}}]}, "affected": [{"source": "disclosure@vulncheck.com", "affectedData": [{"vendor": "thorsten", "product": "phpMyFAQ", "versions": [{"status": "affected", "version": "0", "lessThan": "4.1.6", "versionType": "semver"}, {"status": "unaffected", "version": "4.1.6", "versionType": "semver"}], "defaultStatus": "unaffected"}]}], "published": "2026-07-27T16:18:12.633", "references": [{"url": "https://github.com/thorsten/phpMyFAQ/security/advisories/GHSA-28cc-v39j-vr95", "source": "disclosure@vulncheck.com"}, {"url": "https://www.vulncheck.com/advisories/phpmyfaq-before-privilege-escalation-via-group-membership", "source": "disclosure@vulncheck.com"}, {"url": "https://github.com/thorsten/phpMyFAQ/security/advisories/GHSA-28cc-v39j-vr95", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"}], "vulnStatus": "Deferred", "weaknesses": [{"type": "Secondary", "source": "disclosure@vulncheck.com", "description": [{"lang": "en", "value": "CWE-269"}]}], "descriptions": [{"lang": "en", "value": "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."}], "lastModified": "2026-07-28T16:20:14.670", "sourceIdentifier": "disclosure@vulncheck.com"}