CVE-2025-40779
Kea crash upon interaction between specific client options and subnet selection
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
7.5
Kea crash upon interaction between specific client options and subnet selection
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.
- Record
CVE-2025-40779- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-476
- Updated
- 2026-11-02
EUVDEUVD-2025-27981
7.5
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.
- Record
EUVD-2025-27981- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-v32h-8f7r-3543
7.5
If a DHCPv4 client sends a request with some specific options, and Kea fails to find an...
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.
- Record
GHSA-v32h-8f7r-3543- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-476
- Updated
- 2026-11-02
NVD
7.5
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.
- Record
CVE-2025-40779- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-476
- Updated
- 2026-11-02
OSV
7.5
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.
- Record
CVE-2025-40779- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSVRHSA-2025:21006
7.5
Red Hat Security Advisory: kea security update
- Record
RHSA-2025:21006- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSVUBUNTU-CVE-2025-40779
7.5
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.
- Record
UBUNTU-CVE-2025-40779- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSVopenSUSE-SU-2025:15499-1 No score
kea-3.0.1-1.1 on GA media
These are all security issues fixed in the kea-3.0.1-1.1 package on the GA media of openSUSE Tumbleweed.
- Record
openSUSE-SU-2025:15499-1- Updated
- 2026-11-02
OSVopenSUSE-SU-2026:20341-1 No score
Security update for kea
This update for kea fixes the following issues:
Update to release 3.0.1:
- CVE-2025-40779: Fixed crash upon interaction between specific client options and subnet selection (bsc#1248801).
- Record
openSUSE-SU-2026:20341-1- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
kea-debuginfoRed Hat:enterprise_linux:10.1 |
before 0:3.0.1-1.el10_1 | 0:3.0.1-1.el10_1 |
kea-debugsourceRed Hat:enterprise_linux:10.1 |
before 0:3.0.1-1.el10_1 | 0:3.0.1-1.el10_1 |
kea-devel-debuginfoRed Hat:enterprise_linux:10.1 |
before 0:3.0.1-1.el10_1 | 0:3.0.1-1.el10_1 |
kea-docRed Hat:enterprise_linux:10.1 |
before 0:3.0.1-1.el10_1 | 0:3.0.1-1.el10_1 |
kea-hooksRed Hat:enterprise_linux:10.1 |
before 0:3.0.1-1.el10_1 | 0:3.0.1-1.el10_1 |
kea-hooks-debuginfoRed Hat:enterprise_linux:10.1 |
before 0:3.0.1-1.el10_1 | 0:3.0.1-1.el10_1 |
kea-keama-debuginfoRed Hat:enterprise_linux:10.1 |
before 0:3.0.1-1.el10_1 | 0:3.0.1-1.el10_1 |
kea-libs-debuginfoRed Hat:enterprise_linux:10.1 |
before 0:3.0.1-1.el10_1 | 0:3.0.1-1.el10_1 |
keaRed Hat:enterprise_linux:10.1 |
before 0:3.0.1-1.el10_1 | 0:3.0.1-1.el10_1 |
kea-libsRed Hat:enterprise_linux:10.1 |
before 0:3.0.1-1.el10_1 | 0:3.0.1-1.el10_1 |
kea-keamaRed Hat:enterprise_linux:10.1 |
before 0:3.0.1-1.el10_1 | 0:3.0.1-1.el10_1 |
keaopenSUSE:Tumbleweed |
before 3.0.1-1.1 | 3.0.1-1.1 |
keaopenSUSE:Leap 16.0 |
before 3.0.1-160000.1.1 | 3.0.1-160000.1.1 |
History
| Recorded | Changed | Sources |
|---|---|---|
| affected | ||
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2025-40779 is a high vulnerability (CVSS 7.5) in Isc Kea, published August 27, 2025. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.54%, the 45th percentile. Fixed in kea-debuginfo 0:3.0.1-1.el10_1.
References
kb.isc.org/docs/cve-2025-40779
openwall.com/lists/oss-security/2025/08/27/1
nvd.nist.gov/vuln/detail/CVE-2025-40779
github.com/advisories/GHSA-v32h-8f7r-3543
security-tracker.debian.org/tracker/CVE-2025-40779
access.redhat.com/errata/RHSA-2025:21006
Show 10 moreShow less
access.redhat.com/security/updates/classification
bugzilla.redhat.com/show_bug.cgi?id=2391373
security.access.redhat.com/data/csaf/v2/advisories/2025/rhsa-2025_21006.json
access.redhat.com/security/cve/CVE-2025-40779
cve.org/CVERecord?id=CVE-2025-40779
ubuntu.com/security/CVE-2025-40779
gitlab.isc.org/isc-projects/kea/-/commit/0afd42b5dfb2e547b3c25023953892c1e578aba3
gitlab.isc.org/isc-projects/kea/-/commit/b25d7e8a81273e4099bf6c7f639ed774de2f3d08
suse.com/security/cve/CVE-2025-40779
bugzilla.suse.com/1248801