CVE-2025-20243

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

Description

A vulnerability in the management and VPN web servers of Cisco Secure Firewall ASA Software and Secure FTD Software could allow an unauthenticated, remote attacker to cause the device to reload unexpectedly, resulting in a DoS condition. This vulnerability is due to improper validation of user-supplied input on an interface with VPN web services. An attacker could exploit this vulnerability by sending crafted HTTP requests to a targeted web server on an affected device. A successful exploit could allow the attacker to cause a DoS condition when the device reloads.

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-2025-20243?
CVE-2025-20243 has been scored as a high severity vulnerability.
How to fix CVE-2025-20243?
To fix CVE-2025-20243, 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-2025-20243 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2025-20243 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-2025-20243?
CVE-2025-20243 affects Cisco Cisco Adaptive Security Appliance (ASA) Software, Cisco Cisco Firepower Threat Defense Software.
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