Vulnerability · Published Mar 4, 2026 · Assigned by cisco
CVE-2026-20073Cisco Secure Firewall Adaptive Security Appliance Software and Cisco Secure Firewall Threat Defense Software Access Control List Bypass Vulnerability
Medium 5.8
In plain English
A medium-severity improper access control in Cisco Secure Firewall Adaptive Security Appliance (ASA) Software from Cisco. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 37% of all known vulnerabilities).
Official description
A vulnerability in Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to send traffic that should be denied through an affected device. This vulnerability is due to improper error handling when an affected device that is joining a cluster runs out of memory while replicating access control rules. An attacker could exploit this vulnerability by sending traffic that should be blocked through the device. A successful exploit could allow the attacker to bypass access controls and reach devices in protected networks.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Cisco | Cisco Secure Firewall Adaptive Security Appliance (ASA) Software | 9.12.39.12.19.12.29.12.49.12.3.29.12.3.79.12.2.59.12.3.12 |
| Cisco | Cisco Secure Firewall Threat Defense (FTD) Software | 6.4.0.16.4.0.26.4.0.56.4.06.4.0.36.4.0.46.4.0.66.4.0.7 |
Weakness: CWE-284 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N