CVE-2026-20349: Cisco ASA and FTD Firewalls Face Remote DoS in SSL VPN, Already Exploited
Cisco has disclosed a high-severity denial-of-service vulnerability affecting its Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense products. The flaw, tracked as CVE-2026-20349, resides in the SSL VPN component and allows unauthenticated remote attackers to trigger device reboots by sending specially crafted HTTP requests. The issue also impacts FTD deployments using Zero Trust Network Access. With a CVSS v3.1 base score of 8.6, the vulnerability has already been observed in active exploitation campaigns since August 2026. Cisco released hotfixes for both affected platforms and strongly urges immediate updates, while confirming that Secure Firewall Management Center remains unaffected.
Security NEXTAug 12, 2026Translated from Japanese