Buffer overflow in Cisco Adaptive Security Appliance (Asa) Software
CVE-2025-20363
A vulnerability in the web services of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software, Cisco Secure Firewall Threat Defense (FTD) Software, Cisco IOS Software, Cisco IOS XE Software, and Cisco IOS XR Software could allow…
Vulnerability class: Buffer Overflow
EPSS: 0.064 (91.2th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 9.0 (Critical). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H.
Affected products
- Cisco Adaptive Security Appliance (Asa) Software — versions 9.8.1, 9.8.1.5, 9.8.1.7
- Cisco Firepower Threat Defense Software — versions 6.2.3, 6.2.3.1, 6.2.3.2
- Cisco Ios Xe Software — versions 3.2.0SG, 3.2.1SG, 3.2.2SG
- Cisco Ios Xr Software — versions 6.5.1, 6.5.2, 6.5.3
- Cisco Ios — versions 12.2(15)B, 12.2(16)B1, 12.2(16)B2
Weakness classification (CWE)
Public proof-of-concept exploits
References
Frequently asked questions
- What is CVE-2025-20363?
- CVE-2025-20363 is a critical-severity vulnerability in Cisco Adaptive Security Appliance (Asa) Software, classified under Heap-based Buffer Overflow. CVSS score: 9.0/10. Published 2025-09-25.
- How severe is CVE-2025-20363?
- Critical severity. CVSS v3 base score is 9.0 out of 10.
- Is CVE-2025-20363 known to be exploited?
- 2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.