Secure Firewall ASA and FTD
CVE-2024-20293: A vulnerability in the activation of an access control list (ACL) on Cisco Adaptive Security Appliance (ASA…
A vulnerability in the activation of an access control list (ACL) on Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to bypass the protection that is offered by a configured ACL 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 9.19 | 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 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 |
Always confirm against the vendor advisory, which lists every fixed hotfix.
What it is
A vulnerability in the activation of an access control list (ACL) on Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to bypass the protection that is offered by a configured ACL on an affected device. This vulnerability is due to a logic error that occurs when an ACL changes from inactive to active in the running configuration of an affected device. An attacker could exploit this vulnerability by sending traffic through the affected device that should be denied by the configured ACL. The reverse condition is also true—traffic that should be permitted could be denied by the configured ACL. A successful exploit could allow the attacker to bypass configured ACL protections on the affected device, allowing the attacker to access trusted networks that the device might be protecting. Note: This vulnerability applies to both IPv4 and IPv6 traffic as well as dual-stack ACL configurations in which both IPv4 and IPv6 ACLs are configured on an interface.
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.