CVE-2025-20134

High

Description

A vulnerability in the certificate processing of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause the device to reload unexpectedly, resulting in a denial of service (DoS) condition. This vulnerability is due to improper parsing of SSL/TLS certificates. An attacker could exploit this vulnerability by sending crafted DNS packets that match a static Network Address Translation (NAT) rule with DNS inspection enabled through an affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition.

SeverityHigh
CVSS8.6
Exploit probability—
ProductCisco Adaptive Security Appliance (ASA) Software
PublishedAug 14, 2025
First seenAug 14, 2025
Weakness typeCWE-415CWE-415

How to fix

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

Affected products

ProductAffected versionsFixed in
Cisco Cisco Adaptive Security Appliance (ASA) Software9.12.4.39, 9.12.4.40, 9.14.4.6, 9.14.4.7, 9.12.4.41, 9.12.4.47, 9.14.4.12, 9.12.4.48, 9.14.4.13, 9.12.4.50, 9.14.4.14, 9.12.4.52, 9.14.4.15, 9.12.4.54, 9.14.4.17, 9.12.4.55, 9.14.4.22, 9.14.4.23, 9.12.4.56, 9.12.4.58, 9.12.4.62, 9.12.4.65, 9.12.4.67, 9.14.4.24—
Cisco Cisco Firepower Threat Defense Software6.6.5.2, 6.4.0.15, 6.6.7, 6.4.0.16, 6.6.7.1, 6.4.0.17, 6.6.7.2, 6.4.0.18—

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