Vulnerability in Cisco Adaptive Security Appliance (Asa) Software
CVE-2025-20243
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.
EPSS: 0.006 (45.7th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 8.6 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H.
Affected products
- Cisco Adaptive Security Appliance (Asa) Software — versions 9.12.3, 9.8.3, 9.12.1
- Cisco Firepower Threat Defense Software — versions 6.2.3.14, 6.4.0.1, 6.2.3.7
Weakness classification (CWE)
References
Frequently asked questions
- What is CVE-2025-20243?
- CVE-2025-20243 is a high-severity vulnerability in Cisco Adaptive Security Appliance (Asa) Software, classified under Loop with Unreachable Exit Condition (Infinite Loop). CVSS score: 8.6/10. Published 2025-08-14.
- How severe is CVE-2025-20243?
- High severity. CVSS v3 base score is 8.6 out of 10.