CVE-2025-20134

Cisco Adaptive Security Appliance and Firepower Threat Defense Software SSL/TLS Certificate Denial of Service Vulnerability

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.

Category

8.6
CVSS
Severity: High
CVSS 3.1 •
EPSS 0.08%
Affected: Cisco Cisco Adaptive Security Appliance (ASA) Software
Affected: Cisco Cisco Firepower Threat Defense Software
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2025-20134?
CVE-2025-20134 has been scored as a high severity vulnerability.
How to fix CVE-2025-20134?
To fix CVE-2025-20134, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2025-20134 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2025-20134 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2025-20134?
CVE-2025-20134 affects Cisco Cisco Adaptive Security Appliance (ASA) Software, Cisco Cisco Firepower Threat Defense Software.
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