Fortinet FortiGate Under Active Attack Through SAML SSO Authentication Bypass

Threat actors have begun to exploit two newly disclosed security flaws in Fortinet FortiGate devices, less than a week after public disclosure. Cybersecurity company Arctic Wolf said it observed active intrusions involving malicious single sign-on (SSO) logins on FortiGate appliances on December 12, 2025. The attacks exploit two critical authentication bypasses (CVE-2025-59718 and CVE-2025-59719