Unchecked Return Value to NULL Pointer Dereference in Cisco Secure Firewall Threat Defense (FTD) and Cisco Secure Firewall Adaptive Security Appliance (ASA) - CVE-2026-76418
Published: October 28, 2026
Vulnerability identifier: #VU158351
CSH Severity: High
CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-76418
CWE-ID: CWE-690
Exploitation vector: Remote access
Exploit availability:
The vulnerability is being exploited in the wild
Vulnerability details
The vulnerability allows a remote attacker to perform a denial of service attack.
The vulnerability exists due to a logic error when secondary authentication is configured on a tunnel group. A remote attacker can send specially crafted request when connecting to the SSL remote access VPN and perform a denial of service attack.
Note, the vulnerability is being actively exploited in the wild.
Affected software
Cisco Secure Firewall Threat Defense (FTD)
Cisco Secure Firewall Adaptive Security Appliance (ASA)
Cisco Secure Firewall Adaptive Security Appliance (ASA)
How to mitigate CVE-2026-76418
Install updates from vendor's website.
Cisco Secure Firewall Threat Defense (FTD) - addressed in versions 7.0.11, 7.2.13, 7.4.9, 7.6.7, 7.7.14, 10.0.3, 10.1.1
Cisco Secure Firewall Adaptive Security Appliance (ASA) - addressed in versions 9.16.4.104, 9.18.4.96, 9.20.4.50, 9.22.3.200, 9.23.1.48, 9.24.1.27, 9.24.10.1
Cisco Secure Firewall Adaptive Security Appliance (ASA) - addressed in versions 9.16.4.104, 9.18.4.96, 9.20.4.50, 9.22.3.200, 9.23.1.48, 9.24.1.27, 9.24.10.1