Secure Firewall ASA and FTD
CVE-2024-20426: A vulnerability in the Internet Key Exchange version 2 (IKEv2) protocol for VPN termination of Cisco Adapti…
A vulnerability in the Internet Key Exchange version 2 (IKEv2) protocol for VPN termination of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device.
Published
Automatic summary from the vendor's CVE record. We haven't written a full analysis of this vulnerability yet.
Affected and fixed versions
| Product / branch | Fixed in |
|---|---|
| Cisco Adaptive Security Appliance (ASA) Software 9.18 | See the advisory |
| Cisco Adaptive Security Appliance (ASA) Software 9.18 | See the advisory |
| Cisco Adaptive Security Appliance (ASA) Software 9.18 | See the advisory |
| Cisco Adaptive Security Appliance (ASA) Software 9.18 | See the advisory |
| Cisco Adaptive Security Appliance (ASA) Software 9.18 | See the advisory |
| Cisco Adaptive Security Appliance (ASA) Software 9.18 | See the advisory |
| Cisco Adaptive Security Appliance (ASA) Software 9.18 | See the advisory |
| Cisco Adaptive Security Appliance (ASA) Software 9.18 | See the advisory |
| Cisco Adaptive Security Appliance (ASA) Software 9.18 | See the advisory |
| Cisco Adaptive Security Appliance (ASA) Software 9.18 | See the advisory |
| Cisco Adaptive Security Appliance (ASA) Software 9.18 | See the advisory |
| Cisco Adaptive Security Appliance (ASA) Software 9.18 | See the advisory |
| Cisco Adaptive Security Appliance (ASA) Software 9.18 | See the advisory |
| Cisco Adaptive Security Appliance (ASA) Software 9.18 | See the advisory |
| Cisco Adaptive Security Appliance (ASA) Software 9.18 | See the advisory |
| Cisco Adaptive Security Appliance (ASA) Software 9.18 | See the advisory |
| Cisco Adaptive Security Appliance (ASA) Software 9.18 | See the advisory |
| Cisco Adaptive Security Appliance (ASA) Software 9.18 | See the advisory |
| Cisco Adaptive Security Appliance (ASA) Software 9.19 | See the advisory |
| Cisco Adaptive Security Appliance (ASA) Software 9.19 | See the advisory |
| Cisco Adaptive Security Appliance (ASA) Software 9.19 | See the advisory |
| Cisco Adaptive Security Appliance (ASA) Software 9.19 | See the advisory |
| Cisco Adaptive Security Appliance (ASA) Software 9.19 | See the advisory |
| Cisco Adaptive Security Appliance (ASA) Software 9.19 | See the advisory |
| Cisco Adaptive Security Appliance (ASA) Software 9.19 | See the advisory |
| Cisco Adaptive Security Appliance (ASA) Software 9.19 | See the advisory |
| Cisco Adaptive Security Appliance (ASA) Software 9.19 | See the advisory |
| Cisco Adaptive Security Appliance (ASA) Software 9.19 | See the advisory |
| Cisco Adaptive Security Appliance (ASA) Software 9.20 | See the advisory |
| Cisco Adaptive Security Appliance (ASA) Software 9.20 | See the advisory |
| Cisco Adaptive Security Appliance (ASA) Software 9.20 | See the advisory |
| Cisco Adaptive Security Appliance (ASA) Software 9.20 | See the advisory |
| Cisco Adaptive Security Appliance (ASA) Software 9.20 | See the advisory |
| Cisco Firepower Threat Defense Software 7.2 | See the advisory |
| Cisco Firepower Threat Defense Software 7.2 | See the advisory |
| Cisco Firepower Threat Defense Software 7.2 | See the advisory |
| Cisco Firepower Threat Defense Software 7.2 | See the advisory |
| Cisco Firepower Threat Defense Software 7.2 | See the advisory |
| Cisco Firepower Threat Defense Software 7.2 | See the advisory |
| Cisco Firepower Threat Defense Software 7.2 | See the advisory |
| Cisco Firepower Threat Defense Software 7.2 | See the advisory |
| Cisco Firepower Threat Defense Software 7.2 | See the advisory |
| Cisco Firepower Threat Defense Software 7.2 | See the advisory |
| Cisco Firepower Threat Defense Software 7.2 | See the advisory |
| Cisco Firepower Threat Defense Software 7.2 | See the advisory |
| Cisco Firepower Threat Defense Software 7.2 | See the advisory |
| Cisco Firepower Threat Defense Software 7.2 | See the advisory |
| Cisco Firepower Threat Defense Software 7.3 | See the advisory |
| Cisco Firepower Threat Defense Software 7.3 | See the advisory |
| Cisco Firepower Threat Defense Software 7.3 | See the advisory |
| Cisco Firepower Threat Defense Software 7.3 | See the advisory |
| Cisco Firepower Threat Defense Software 7.4 | See the advisory |
| Cisco Firepower Threat Defense Software 7.4 | See the advisory |
| Cisco Firepower Threat Defense Software 7.4 | See the advisory |
Always confirm against the vendor advisory, which lists every fixed hotfix.
What it is
A vulnerability in the Internet Key Exchange version 2 (IKEv2) protocol for VPN termination of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to insufficient input validation. An attacker could exploit this vulnerability by sending crafted IKEv2 traffic to an affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition.
Exploitation
The Cisco Product Security Incident Response Team (PSIRT) is not aware of any public announcements or malicious use of the vulnerability that is described in this advisory.
Sources
KEV status, EPSS score and vendor data refreshed automatically, last on 11 Oct 2026.