Advisories

Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense Software IKEv2 Certificate Authentication Denial of Service Vulnerability

A vulnerability in the certification authentication feature of Internet Key Exchange version 2 (IKEv2) for Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause an affected device to reload unexpectedly. This vulnerability is due to a logic error during the certificate authentication phase of the IKEv2 connection setup. An attacker could exploit this vulnerability by attempting to establish an IKEv2 VPN connection with a crafted certificate. A successful exploit could allow the attacker to cause the IKEv2 process to crash, causing a denial of service (DoS) condition. Ci

Read at Cisco PSIRT Security Advisories

Vendor

Cisco

Product

ASA, Firepower / FTD

Fix

available

Exposure class

Edge / VPN / firewall

• Cisco PSIRT Security Advisories (sec.cloudapps.cisco.com)
• CVE-2026-20249 on this site · NVD · CVE.org · Vulnpedia

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