What’s Vulnerable › Vulnerabilities
CVE-2025-20134: Cisco Adaptive Security Appliance and Firepower Threat Defense Software SSL/TLS Certificate Denial of Service Vulnerability
- Severity: high (CVSS 8.6 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 0.4% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2025-08-14 · updated 2026-06-17
- Weakness: CWE-415
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.
Affected products
- Cisco ASA Software: 9.12.4.39, 9.12.4.40, 9.14.4.6, 9.14.4.7, 9.12.4.41, 9.12.4.47 (+18)
- Cisco Firepower Threat Defense Software: 6.6.5.2, 6.4.0.15, 6.6.7, 6.4.0.16, 6.6.7.1, 6.4.0.17 (+2)
References
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