CVE-2026-20073

Medium

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.

SeverityMedium
CVSS5.8
Exploit probability—
ProductCisco Adaptive Security Appliance Software
PublishedMar 4, 2026
First seenMar 4, 2026

How to fix

Sources list no fixed version or patch link for this vulnerability.

Affected products

ProductAffected versionsFixed in
cisco adaptive_security_appliance_software9.12.1, 9.12.1.2, 9.12.1.3, 9.12.2, 9.12.2.1, 9.12.2.4, 9.12.2.5, 9.12.2.9, 9.12.3, 9.12.3.2, 9.12.3.7, 9.12.3.9, 9.12.3.12, 9.12.4, 9.12.4.2, 9.12.4.4, 9.12.4.7, 9.12.4.8, 9.12.4.10, 9.12.4.13, 9.12.4.18, 9.12.4.24, 9.12.4.26, 9.12.4.29, 9.12.4.30, 9.12.4.35, 9.12.4.37, 9.12.4.38, 9.12.4.39, 9.12.4.40, 9.12.4.41, 9.12.4.47, 9.12.4.48, 9.12.4.50, 9.12.4.52, 9.12.4.54, 9.12.4.55, 9.12.4.56, 9.12.4.58, 9.12.4.62, 9.12.4.65, 9.12.4.67, 9.16.1, 9.16.1.28, 9.16.2, 9.16.2.3, 9.16.2.7, 9.16.2.11, 9.16.2.13, 9.16.2.14, 9.16.3, 9.16.3.3, 9.16.3.14, 9.16.3.15, 9.16.3.19, 9.16.3.23, 9.16.4, 9.16.4.9, 9.16.4.14, 9.16.4.19, 9.16.4.27, 9.16.4.38, 9.16.4.39, 9.16.4.42, 9.16.4.48, 9.16.4.55, 9.16.4.57, 9.16.4.61, 9.16.4.62, 9.16.4.67, 9.16.4.70, 9.16.4.71, 9.16.4.76, 9.16.4.82, 9.16.4.84, 9.17.1, 9.17.1.7, 9.17.1.9, 9.17.1.10, 9.17.1.11, 9.17.1.13, 9.17.1.15, 9.17.1.20, 9.17.1.30, 9.17.1.33, 9.17.1.39, 9.17.1.45, 9.17.1.46, 9.18.1, 9.18.1.3, 9.18.2, 9.18.2.5, 9.18.2.7, 9.18.2.8, 9.18.3, 9.18.3.39, 9.18.3.46, 9.18.3.53, 9.18.3.55, 9.18.3.56, 9.18.4, 9.18.4.5, 9.18.4.8, 9.18.4.22, 9.18.4.24, 9.18.4.29, 9.18.4.34, 9.18.4.40, 9.18.4.47, 9.18.4.50, 9.18.4.52, 9.18.4.53, 9.18.4.57, 9.18.4.66, 9.18.4.67, 9.19.1, 9.19.1.5, 9.19.1.9, 9.19.1.12, 9.19.1.18, 9.19.1.22, 9.19.1.24, 9.19.1.27, 9.19.1.28, 9.19.1.31, 9.19.1.37, 9.19.1.38, 9.19.1.42, 9.20.1, 9.20.1.5, 9.20.2, 9.20.2.10, 9.20.2.21, 9.20.2.22, 9.20.3, 9.20.3.4, 9.20.3.7, 9.20.3.9, 9.20.3.10, 9.20.3.13, 9.20.3.16, 9.20.3.20, 9.20.4, 9.20.4.7, 9.20.4.10, 9.22.1.1, 9.22.1.2, 9.22.1.3, 9.22.1.6, 9.22.2, 9.22.2.4, 9.22.2.9, 9.22.2.13, 9.23.1, 9.23.1.3, 9.23.1.7, 9.23.1.13, 9.23.1.19—
cisco secure_firewall_threat_defense6.4.0, 6.4.0.1, 6.4.0.2, 6.4.0.3, 6.4.0.4, 6.4.0.5, 6.4.0.6, 6.4.0.7, 6.4.0.8, 6.4.0.9, 6.4.0.10, 6.4.0.11, 6.4.0.12, 6.4.0.13, 6.4.0.14, 6.4.0.15, 6.4.0.16, 6.4.0.17, 6.4.0.18, 7.0.0, 7.0.0.1, 7.0.1, 7.0.1.1, 7.0.2, 7.0.2.1, 7.0.3, 7.0.4, 7.0.5, 7.0.6, 7.0.6.1, 7.0.6.2, 7.0.6.3, 7.0.7, 7.0.8, 7.0.8.1, 7.1.0, 7.1.0.1, 7.1.0.2, 7.1.0.3, 7.2.0, 7.2.0.1, 7.2.1—

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