Auth bypass in Thorsten Phpmyfaq
CVE-2026-111911
phpMyFAQ 4.0.0 before 4.1.9 contains an authentication bypass vulnerability where WebAuthn registration endpoints attach credentials to any account without authentication or challenge validation. Attackers can stage a victim username, submit a forged fmt=none attestation to register a passkey, then log in bypassing passwords and TOTP for account takeover.
Vulnerability class: Broken Authentication
Published · last modified .
CVSS v3 metric
CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
Weakness classification (CWE)
References
- github.com/thorsten/phpMyFAQ/security/advisories/GHSA-g6cq-6rqg-6c9p (vendor-advisory)
- github.com/thorsten/phpMyFAQ/security/advisories/GHSA-rg9h-f29v-xhxr (vendor-advisory)
- www.vulncheck.com/advisories/phpmyfaq-4.0.0-before-4.1.9-authentication-bypass-… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-111911?
- CVE-2026-111911 is a critical-severity vulnerability in Thorsten Phpmyfaq, classified under Improper Authentication. CVSS score: 9.8/10. Published 2026-10-17.
- How severe is CVE-2026-111911?
- Critical severity. CVSS v3 base score is 9.8 out of 10.