What is CVE-2025-20253?

CVE-2025-20253 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-2025-20253?

High severity. CVSS v3 base score is 8.6 out of 10.

Vulnerability in Cisco Adaptive Security Appliance (Asa) Software

CVE-2025-20253

A vulnerability in the IKEv2 feature of Cisco IOS Software, IOS XE Software, Secure Firewall ASA Software, and Secure FTD Software could allow an unauthenticated, remote attacker to cause the device to reload, resulting in a DoS condition…

EPSS: 0.001 (19.8th 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)

CWE-835 — Loop with Unreachable Exit Condition (Infinite Loop)

References

cisco-sa-asa-ftd-ios-dos-DOESHWHy

Frequently asked questions

What is CVE-2025-20253?: CVE-2025-20253 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-2025-20253?: High severity. CVSS v3 base score is 8.6 out of 10.