23 Oct 2026 15:48:27 UTC
Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense Software IKEv2 Certificate Authentication Denial of Service Vulnerability
cve-program · CVE-2026-20249 · Published
CVE-2026-20249
Cisco Secure Firewall Adaptive Security Appliance (ASA) Software · denial of service
CVSS 3.1 8.6 HIGHCheck source for fixed versionsKEV status unknown
cve-program · CVE-2026-20249
PublishedA 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.
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