High severity · published Aug 27, 2025
CVE-2025-40779
Kea crash upon interaction between specific client options and subnet selection
7.5
CVSS
0.5%
EPSS
No
On KEV
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 vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 45% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
KE
Kea · ISC
2.7.1 through 2.7.9; 3.0.0; 3.1.0 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-40779
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-40779
kb.isc.org
https://kb.isc.org/docs/cve-2025-40779
security-tracker.debian.org
https://security-tracker.debian.org/tracker/CVE-2025-40779
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