CVE-2026-85590 phpMyFAQ before 4.1.8 Authentication Bypass via Two-Factor Disable
An attacker with a hijacked session can disable two-factor authentication, enabling password-only access to any account, including administrators.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-85590?
CVE-2026-85590 is a high-severity authentication bypass vulnerability in thorsten phpMyFAQ, published on 4 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
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.
Weakness: CWE-308
Which versions are affected by CVE-2026-85590?
How do I fix CVE-2026-85590?
No fix has been published for CVE-2026-85590 yet. Limit exposure of the affected software until one is available.
Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.
Is CVE-2026-85590 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-85590 exists.
Sources
Also known as GHSA-h96g-59xp-7r5m, GHSA-x283-48fh-hc5w.