Hackers Exploiting Three-Year-Old FortiGate Vulnerability to Bypass 2FA on Firewalls

**Executive summary:** Attackers are actively abusing Fortinet FortiGate CVE-2020-12812 (FG-IR-19-283) by exploiting a username case-sensitivity mismatch between FortiGate and LDAP to bypass 2FA and gain VPN or admin access; Fortinet documents observed probes and urges immediate patching, configuration changes (disable username case sensitivity or remove LDAP group fallbacks), credential resets, and log audits to detect compromise.