Vulnerability in Cisco Adaptive Security Appliance Software
CVE-2026-20012
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.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.6 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H.
EPSS exploit prediction
EPSS: 0.004 (27.5th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 27th percentile — 27.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000
Affected products
- Cisco Adaptive Security Appliance Software — versions 9.12.1, 9.12.1.2, 9.12.1.3
- Cisco iOS Xe Software — versions 3.5.0E, 3.5.1E, 3.5.2E
- Cisco Secure Firewall Adaptive Security Appliance (Asa) Software — versions 9.8.1, 9.8.1.5, 9.8.1.7
- Cisco Secure Firewall Threat Defense (Ftd) Software — versions 6.2.3, 6.2.3.1, 6.2.3.2
- Cisco iOS — versions 15.2(4)ec2, 15.2(4)jb1, 15.0(2)SE10a
- Cisco iOS Xe — versions 16.10.1, 16.10.1a, 16.10.1b
- Cisco Secure Firewall Threat Defense — versions 6.2.3, 6.2.3.1, 6.2.3.10
Weakness classification (CWE)
References
Frequently asked questions
- What is CVE-2026-20012?
- CVE-2026-20012 is a high-severity vulnerability in Cisco Adaptive Security Appliance Software, classified under Missing Release of Memory after Effective Lifetime. CVSS score: 8.6/10. Published 2026-03-25.
- How severe is CVE-2026-20012?
- High severity. CVSS v3 base score is 8.6 out of 10.