CVE-2025-20133

Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense Software Remote Access SSL VPN Authentication Targeted Denial of Service Vulnerability

Description

A vulnerability in the management and VPN web servers of the Remote Access SSL VPN feature of Cisco Secure Firewall ASA Software and Secure FTD Software could allow an unauthenticated, remote attacker to cause the device to unexpectedly stop responding, resulting in a DoS condition. This vulnerability is due to ineffective validation of user-supplied input during the Remote Access SSL VPN authentication process. An attacker could exploit this vulnerability by sending a crafted request to the VPN service on an affected device. A successful exploit could allow the attacker to cause a DoS condition where the device stops responding to Remote Access SSL VPN authentication requests.

Category

8.6
CVSS
Severity: High
CVSS 3.1 •
EPSS 0.06%
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-2025-20133?
CVE-2025-20133 has been scored as a high severity vulnerability.
How to fix CVE-2025-20133?
To fix CVE-2025-20133, 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-2025-20133 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2025-20133 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-2025-20133?
CVE-2025-20133 affects Cisco Cisco Adaptive Security Appliance (ASA) Software, Cisco Cisco Firepower Threat Defense Software.
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