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.
Published · last modified .
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.
EPSS exploit prediction
EPSS: 0.006 (48.3th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 48th percentile — 48.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.006 · newest: 0.006 · change: +0.000
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.