Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Buffer Vulnerability

published 2025-08-14 14 mo ago modified 2026-06-17 4 mo ago also EUVD-2025-24847

cvss: 8.6; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.7%; EPSS 0.7% chance of exploitation in 30 days, percentile 51%
public exploits: 0; none known

A vulnerability in the RADIUS proxy feature for the IPsec VPN feature of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition.

This vulnerability is due to improper processing of IPv6 packets. An attacker could exploit this vulnerability by sending IPv6 packets over an IPsec VPN connection to an affected device. A successful exploit could allow the attacker to trigger a reload of the device, resulting in a DoS condition.

CISA SSVC

Exploitation: none
Automatable: yes
Technical impact: partial
Assessed: 14 mo ago (2025-08-14)

Exploit prediction

0.66% chance of exploitation in the next 30 days, higher than 51% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	8.6	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

Affected products

Cisco Cisco Firepower Threat Defense Software

Classification

Weakness

CWE-120 Buffer Copy without Checking Size of Input

References

sec.cloudapps.cisco.com /security/center/content/CiscoSecurityAdvisory/cisco-sa-fp2k-IPsec-dos-tjwgdZCO

Sources

CVE List CVE-2025-20222
NVD CVE-2025-20222

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Summary