Vulnerability in Cisco Adaptive Security Appliance (Asa) Software

CVE-2025-20254

A vulnerability in the Internet Key Exchange Version 2 (IKEv2) module of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to trigger a memory leak, resulting in a denial of service (DoS) condition. This vulnerability is due to improper parsing of IKEv2 packets. An attacker could exploit this vulnerability by sending a continuous stream of crafted IKEv2 packets to an affected device. A successful exploit could allow the attacker to partially exhaust system memory, causing system instability like being unable to establish new IKEv2 VPN sessions. A manual reboot of the device is required to recover from this condition.

EPSS: 0.004 (33.6th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.8 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2025-20254?
CVE-2025-20254 is a medium-severity vulnerability in Cisco Adaptive Security Appliance (Asa) Software, classified under Missing Release of Memory after Effective Lifetime. CVSS score: 5.8/10. Published 2025-08-14.
How severe is CVE-2025-20254?
Medium severity. CVSS v3 base score is 5.8 out of 10.