Cisco Patches Actively Exploited ASA and FTD VPN Flaw That Can Crash Firewalls

Cisco has released patches for a high-severity vulnerability tracked as CVE-2026-76418 affecting its Secure Firewall Adaptive Security Appliance (ASA) Software and Secure Firewall Threat Defense (FTD) Software. The flaw carries a CVSS score of 8.6 and has been confirmed as actively exploited in the wild. Successful exploitation allows an unauthenticated, remote attacker to crash affected firewalls, potentially causing denial-of-service conditions. The vulnerability resides in the VPN component of the affected products. Cisco urges administrators to apply the patches immediately given the active exploitation status. Organizations relying on Cisco ASA or FTD for perimeter security and VPN termination are at elevated risk.