CVE-2026-20012: cisco adaptive_security_appliance_software

Vulnerability summary

CVE-2026-20012 is a high (CVSS 8.6) vulnerability in cisco adaptive_security_appliance_software. EPSS estimates a 0.35% chance of exploitation in the next 30 days, higher than 27.7% of scored vulnerabilities.

Timeline

1. 25-03-2026
   PublishedVulnerability first disclosed.
2. 26-03-2026
   Last modifiedVulnerability information updated.

Description

A vulnerability in the Internet Key Exchange version 2 (IKEv2) feature of Cisco IOS Software, Cisco IOS XE Software, Cisco Secure Firewall Adaptive Security Appliance (ASA) Software, and Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to trigger a memory leak, resulting in a denial of service (DoS) condition on an affected device. This vulnerability is due to improper parsing of IKEv2 packets. An attacker could exploit this vulnerability by sending crafted IKEv2 packets to an affected device. A successful exploit of Cisco IOS Software and IOS XE Software could allow the attacker to cause the affected device to reload, resulting in a DoS condition. A successful exploit of Cisco Secure Firewall ASA Software and Secure FTD Software could allow the attacker to partially exhaust system memory, resulting in system instability, such as the inability to establish new IKEv2 VPN sessions. A manual reboot of the device is required to recover from this condition.

• CWE-401Missing Release of Memory after Effective LifetimeThe product does not sufficiently track and release allocated memory after it has been used, making the memory unavailable for reallocation and reuse.