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OpenAdvisories
High · 8.6 CVE-2026-20012 EUVD-2026-15428GHSA-5cpj-j8xh-5rgh

A vulnerability in the Internet Key Exchange version 2 (IKEv2) feature of Cisco IOS Software, Cisco IOS XE Software, Cisco Secure Firewall …

Published Mar 25, 2026 · Updated Mar 26, 2026 · Assigned by cisco

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.

Affected products

VendorProductAffectedFixed
Cisco IOS 15.2(1)S, 15.2(2)S, 15.2(1)S1, 15.2(4)S, 15.2(1)S2, 15.2(2)S1, 15.2(2)S2, 15.2(2)S0a, 15.2(2)S0c, 15.2(4)S1, 15.2(4)S4, 15.2(4)S6, 15.2(4)S2, 15.2(4)S5, 15.2(4)S3, 15.2(4)S3a, 15.2(4)S4a, 15.2(4)S7, 15.3(1)T, 15.3(2)T, 15.3(1)T1, 15.3(1)T2, 15.3(1)T3, 15.3(1)T4, 15.3(2)T1, 15.3(2)T2, 15.3(2)T3, 15.… —
Cisco Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.8.1, 9.8.1.5, 9.8.1.7, 9.8.2, 9.8.2.8, 9.8.2.14, 9.8.2.15, 9.8.2.17, 9.8.2.20, 9.8.2.24, 9.8.2.26, 9.8.2.28, 9.8.2.33, 9.8.2.35, 9.8.2.38, 9.8.3.8, 9.8.3.11, 9.8.3.14, 9.8.3.16, 9.8.3.18, 9.8.3.21, 9.8.3, 9.8.3.26, 9.8.3.29, 9.8.4, 9.8.4.3, 9.8.4.7, 9.8.4.8, 9.8.4.10, 9.8.4.12, 9.8.4.15, 9.8.4.17… —
Cisco Cisco IOS XE Software 3.5.0E, 3.5.1E, 3.5.2E, 3.5.3E, 3.11.1S, 3.11.2S, 3.11.0S, 3.11.3S, 3.11.4S, 3.12.0S, 3.12.1S, 3.12.2S, 3.12.3S, 3.12.0aS, 3.12.4S, 3.13.0S, 3.13.1S, 3.13.2S, 3.13.3S, 3.13.4S, 3.13.5S, 3.13.2aS, 3.13.0aS, 3.13.5aS, 3.13.6S, 3.13.7S, 3.13.6aS, 3.13.7aS, 3.13.8S, 3.13.9S, 3.13.10S, 3.6.0E, 3.6.1E, 3… —
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 6.2.3, 6.2.3.1, 6.2.3.2, 6.2.3.3, 6.2.3.4, 6.2.3.5, 6.2.3.6, 6.2.3.7, 6.2.3.8, 6.2.3.10, 6.2.3.11, 6.2.3.9, 6.2.3.12, 6.2.3.13, 6.2.3.14, 6.2.3.15, 6.2.3.16, 6.2.3.17, 6.2.3.18, 6.6.0, 6.6.0.1, 6.6.1, 6.6.3, 6.6.4, 6.6.5, 6.6.5.1, 6.6.5.2, 6.6.7, 6.6.7.1, 6.6.7.2, 6.4.0, 6.4.0.1, 6.4.0.3, 6.4.0.2, … —

Advisories 2

References