SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityDeferred

CVE-2025-40779

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.

HIGH 7.5EPSS 0.54%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.54%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

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.

CVSS 3.1
7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS
0.54% probability · 45th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-476
Source
security-officer@isc.org
EPSS trend
0%3%5%26 October 2026: 0.54%26 October 202626 October 2026

EPSS 0.5% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.