CVE-2025-40779 HIGH

CVE-2025-40779: Kea crash upon interaction between specific client options and subnet selection

Vendor Isc
Product Kea
Weakness CWE-476
Published August 27, 2025
Last update November 4, 2025
View on NVD All CVEs

CVSS base score

7.5/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Confidentiality None
Integrity None

CVSS vector

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

What the vulnerability does

01Description

If a DHCPv4 client sends a request with some specific options, and Kea fails to find an appropriate subnet for the client, the `kea-dhcp4` process will abort with an assertion failure. This happens only if the client request is unicast directly to Kea; broadcast messages do not cause the problem. This issue affects Kea versions 2.7.1 through 2.7.9, 3.0.0, and 3.1.0.

Key dates

02Disclosure timeline

August 27, 2025 CVE published
November 4, 2025 Record updated