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

Cisco patched a critical vulnerability (CVE-2026-76418) in its Secure Firewall ASA and FTD VPN software that allowed remote attackers to crash firewalls via crafted SSL VPN requests, causing denial-of-service. The flaw, exploited in the wild since October 2026, affects devices with secondary authentication enabled on tunnel groups. Cisco released fixes across multiple software versions to address the issue.