CVE-2026-85590 (GCVE-0-2026-85590)

Vulnerability from cvelistv5 – Published: 2026-09-04 11:29 – Updated: 2026-09-04 14:01
VLAI
Title
phpMyFAQ before 4.1.8 Authentication Bypass via Two-Factor Disable
Summary
phpMyFAQ before 4.1.8 contains an authentication bypass vulnerability in its two-factor authentication (TOTP) disable functionality. The removeTwofactorConfig() handler (reachable via POST /api/user/remove-twofactor) verifies only that the user is logged in and that a valid CSRF token is supplied, then disables TOTP without requiring password re-entry or a current TOTP code. The same downgrade is also reachable inline via PUT /api/user/data/update, which accepts a plain twofactor_enabled form field under the same session+CSRF-only guard. An attacker who has hijacked a user's session can silently strip two-factor protection from any account, including administrator accounts, after which password-only authentication succeeds.
Severity
7.1 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-04 13:58 UTC
CWE
  • CWE-308 - Use of Single-factor Authentication
Assigner
VulnCheck CNA under the mitre root
CNA scorecard B 84/100 over 7140 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
thorsten phpMyFAQ Affected: 0 , < 4.1.8 (semver)
Unaffected: 4.1.8 (semver)
    cpe:2.3:a:phpmyfaq:phpmyfaq:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-08-20 00:00
Credits
skeletonsec
Show details on NVD website
To clipboard 

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