High 8.6Published Mar 25, 2026

CVE-2026-20012A 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…

Updated under an hour ago (Oct 27, 2026, 4:50 PM ET)

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It affects Cisco IOS and 6 other products. Add what you run to find out whether that includes you.

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Every CVE for Cisco IOS

Exploited in the last 30 days

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.

CVSS: 8.6 HIGH (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
Weakness (CWE): CWE-401
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: cisco
NVD analysis: Analyzed
Record last updated: Mar 26, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

Cisco IOS cisco:ios (from the name)	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; and 193 more ranges	CNA record
Cisco Cisco Secure Firewall Adaptive Security Appliance (ASA) Software cisco:secure_firewall_adaptive_security_appliance_asa_software (from the name)	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; and 193 more ranges	CNA record
Cisco Cisco IOS XE Software cisco:ios_xe_software (from the name)	3.5.0E; 3.5.1E; 3.5.2E; 3.5.3E; 3.11.1S; 3.11.2S; 3.11.0S; 3.11.3S; and 193 more ranges	CNA record
Cisco Cisco Secure Firewall Threat Defense (FTD) Software cisco:secure_firewall_threat_defense_ftd_software (from the name)	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; and 97 more ranges	CNA record
cisco secure_firewall_threat_defense cisco:secure_firewall_threat_defense	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; and 97 more ranges	NVD
cisco adaptive_security_appliance_software cisco:adaptive_security_appliance_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; and 193 more ranges	NVD
cisco ios cisco:ios	15.0(2)ea; 15.0(2)ea1; 15.0(2)ej; 15.0(2)ej1; 15.0(2)ek; 15.0(2)ek1; 15.0(2)ey; 15.0(2)ey1; and 193 more ranges	NVD
cisco ios_xe cisco:ios_xe	3.5.0e; 3.5.1e; 3.5.2e; 3.5.3e; 3.6.0e; 3.6.1e; 3.6.2ae; 3.6.2e; and 193 more ranges	NVD

References

References

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asa-ftd-ios-dos-kPEpQGGK	vendor-advisory

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.