CVE-2026-20073: cisco adaptive_security_appliance_software Improper Access Control

Vulnerability summary

CVE-2026-20073 is a medium (CVSS 5.8) Improper Access Control vulnerability in cisco adaptive_security_appliance_software. EPSS estimates a 0.40% chance of exploitation in the next 30 days, higher than 33.5% of scored vulnerabilities.

Timeline

1. 04-03-2026
   PublishedVulnerability first disclosed.
2. 04-03-2026
   Last modifiedVulnerability information updated.

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.

• CWE-284Improper Access ControlThe product does not restrict or incorrectly restricts access to a resource from an unauthorized actor.