CVE-2025-20252 (CVSS 5.8)

Description

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.

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CVSS v3.1 Score

5.8

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L

Weakness Type (CWE)

CWE-401 CWE-401

References

Other References

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asa-ftd-ios-dos-DOESHWHy

Frequently Asked Questions

What is CVE-2025-20252? +

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. It has a CVSS v3.1 base score of 5.8 (MEDIUM).

How severe is CVE-2025-20252? +

CVE-2025-20252 has a CVSS v3.1 score of 5.8 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

How do I check if I'm vulnerable to CVE-2025-20252? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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