Cisco Patches Actively Exploited SSL VPN security flaw Affecting ASA and FTD Firewalls

What happened

Cisco has released security updates that address a critical vulnerability in the Remote Access SSL (the encryption that secures a connection to a website) VPN (a service that routes a connection through another network) service on its Secure Firewall Adaptive Security Appliance (ASA) and Threat Defense (FTD) software. Cisco is a telecommunications and networking hardware company based in San Jose, and its products and services include network switches and wireless access points.

Cisco published its advisory on October 28, 2026, after its Product Security Incident Response Team discovered active exploitation of this vulnerability earlier that month.

The advisory does not disclose the identities of the attackers, the victims, or the scale of the campaigns involved. This vulnerability, tracked as CVE-2026-76418 (the public catalogue number for a specific software flaw), lets unauthenticated attackers trigger unexpected device reloads, causing a denial of service.

CVE/vulnerability Cyber Security News Vulnerability 2 min.

The flaw is categorized as high severity, with a CVSS score of 8.6. Cisco SSL VPN Vulnerability The vulnerability stems from logic errors when secondary authentication is configured on a VPN tunnel group. An attacker can send a crafted request while connecting to the SSL remote access VPN, reaching the vulnerable processing path without completing a successful login.