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.

Published: 2025-08-27 Last update: 2026-04-15 Assigner: [email protected] Source: [email protected]
NVD Status：Deferred，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2025-40779 is rated Moderate Risk (43.9/100): CVSS High severity, with low exploitation likelihood (EPSS 0.50%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2025-40779

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.06% 0.50% +0.44%
2 2026-02-04 0.05% 0.06% +0.01%
3 2026-01-23 — 0.05% —

Full EPSS history (9 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-40779

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 3.6 [email protected]

Weakness enumeration for CVE-2025-40779

OS Trackers for CVE-2025-40779

vendor priority summary link
alpine high CVE-2025-40779: 1 source package rows (kea); 9 state rows across 3 repos (3.21-main, 3.22-main, edge-main); fixed 0, open 9. https://security.alpinelinux.org/vuln/CVE-2025-40779
debian unimportant CVE-2025-40779 unimportant priority: Debian including 1 source packages (isc-kea), 4 status rows across 4 suites (bookworm, forky, sid, trixie): resolved 4. https://security-tracker.debian.org/tracker/CVE-2025-40779
redhat high — https://access.redhat.com/security/cve/CVE-2025-40779
suse high CVE-2025-40779 severity important: SUSE including 115 source package names (13.2-9.7:gpg2-2.4.4-4.1, 2.1.3-6.46:gpg2-2.4.4-4.1, …), 379 product×package rows across 27 product lines (Container suse/sl-micro/6.0/baremetal-os-container, Container suse/sl-micro/6.0/base-os-container, … (27 product lines)): Known Not Affected 211, Fixed 138, First Fixed 30. https://www.suse.com/security/cve/CVE-2025-40779/
ubuntu medium CVE-2025-40779 medium priority: Ubuntu including 1 source packages (isc-kea), 8 status rows across 8 suites (bionic, focal, jammy, noble, plucky, questing, upstream, xenial): not-affected 7, needs-triage 1. https://ubuntu.com/security/CVE-2025-40779

Affected software / configurations for CVE-2025-40779

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2025-40779

cvelogic Threat Intelligence