CVE-2026-20013: Cisco Adaptive Security Appliance Software

Medium severity, CVSS 5.8. EPSS: 0.3% chance of exploitation in the next 30 days.

A vulnerability in the IKEv2 feature of Cisco Secure Firewall ASA Software and Cisco Secure FTD Software could allow an unauthenticated, remote attacker to cause a DoS condition on an affected device that may also impact the availability of services to devices elsewhere in the network. This vulnerability is due to memory exhaustion caused by not freeing memory during IKEv2 packet processing. An attacker could exploit this vulnerability by sending crafted IKEv2 packets to an affected device. A successful exploit could allow the attacker to exhaust resources, causing a DoS condition that will eventually require the device to manually reload.

Affected products

• Cisco Adaptive Security Appliance Software: from 9.18.1, before 9.18.4.66 (fixed in 9.18.4.66); from 9.19.1, before 9.20.3.20 (fixed in 9.20.3.20); from 9.22.1.1, before 9.22.2.4 (fixed in 9.22.2.4); from 9.23.1, before 9.23.1.3 (fixed in 9.23.1.3)
• Cisco Secure Firewall Threat Defense: from 7.2.0, before 7.2.11 (fixed in 7.2.11); from 7.3.0, before 7.4.3 (fixed in 7.4.3); from 7.6.0, before 7.6.4 (fixed in 7.6.4); from 7.7.0, before 7.7.10 (fixed in 7.7.10)

Published 2026-03-04. Last modified 2026-08-11.