CVE-2025-40779

Kea crash upon interaction between specific client options and subnet selection

State: Published
Severity: 7.5 High
Published: Aug 27, 2025
Updated: Nov 4, 2025
Reserved: Apr 16, 2025

Description

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.

Scores

CVSS	Score	Vector	Source
3.1	7.5 High	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H	isc

Weaknesses

CWE-476 NULL Pointer Dereference

Affected Products

Product	Versions
KeaISC	2.7.1 through 2.7.9Affected 3.0.0Affected 3.1.0Affected 2.6.0 through 2.6.4Not affected

References

CVE-2025-40779vendor-advisory
http://www.openwall.com/lists/oss-security/2025/08/27/1

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