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vulnerability

Cisco ASA: CVE-2025-20243: Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense Software Remote Access SSL VPN Denial of Service Vulnerabilities

Severity
8
CVSS
(AV:N/AC:L/Au:N/C:N/I:N/A:C)
Published
Aug 14, 2025
Added
Aug 15, 2025
Modified
Mar 25, 2026

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.

Solution

cisco-asa-update-latest
Title
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