CVE-2026-46364: phpMyFAQ has unauthenticated SQL injection via User-Agent header in BuiltinCaptcha

Severity: Critical

CVSS Score: 9.8

phpMyFAQ before 4.1.2 contains an unauthenticated SQL injection vulnerability in BuiltinCaptcha::garbageCollector() and BuiltinCaptcha::saveCaptcha() methods that interpolate unsanitized User-Agent headers into DELETE and INSERT queries. Unauthenticated attackers can exploit the public GET /api/captcha endpoint by crafting malicious User-Agent headers to perform time-based blind SQL injection, extracting sensitive data including user credentials, admin tokens, and SMTP credentials from the database.