Medium · published August 25, 2026
Adminer before 5.4.3 uses a CSRF token scheme that transmits both the XOR mask and the masked value in every token (format (rand XOR secret):rand), allowing anyone who observes a single CSRF token (e.g., via network sniffing, log files, Referrer header, or XSS) to recover the session secret with a single XOR operation and forge unlimited valid tokens. The implementation is further weakened by a low-entropy session token (rand(1,1e6), ~20 bits) that permits blind brute-force, and by use of loose comparison (==) in token verification, enabling PHP type juggling. Exploitation enables cross-site request forgery against authenticated sessions, including execution of arbitrary SQL queries.