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TI-2025-27241 Aliases CVE-2025-40779GHSA-v32h-8f7r-3543

Kea crash upon interaction between specific client options and subnet selection

Priority MEDIUM 40CWE-476Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-476.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00539 45th percentileScored 2026-11-07
Fix Fixed Kea (ISC): 2.6.0Red Hat: 1 advisory

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
ISCKea2.7.1 – 2.7.9; 3.0.0; 3.1.02.6.0Patch availableCNA
  • Kea VendorISC Affected 2.7.1 – 2.7.9; 3.0.0; 3.1.0 Fixed in 2.6.0 Patch available CNA

Remediation

  • Fix · CNA Kea (ISC) Fixed in 2.6.0

Red Hat 1 advisory

  • RHSA-2025:21006 Released 2025-11-11 · Red Hat rating Important
    kea security update
    • Red Hat Enterprise Linux AppStream (v. 10) kea-doc-3.0.1-1.el10_1, kea-hooks-3.0.1-1.el10_1
    • Red Hat Enterprise Linux BaseOS (v. 10) kea-3.0.1-1.el10_1, kea-libs-3.0.1-1.el10_1
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) kea-keama-3.0.1-1.el10_1

Vendor assessments

Red Hat

Red Hat rating: Important. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux AppStream (v. 10)Fixed RHSA-2025:21006
Red Hat Enterprise Linux BaseOS (v. 10)Fixed RHSA-2025:21006
Red Hat Enterprise Linux CodeReady Linux Builder (v. 10)Fixed RHSA-2025:21006

Timeline

  1. 2026-10-02 Threatist record created from CVE-2025-40779
  2. 2026-10-03 Alias added: GHSA-v32h-8f7r-3543
  3. 2026-10-07 Priority changed: LOW → MEDIUM

References

Advisory 1

  • TI-2015-04610 Assertion failure in ISC BIND named via TKEY queries KEVCVSS 3.1HIGH 7.5
  • TI-2023-27571 Certain DNSSEC aspects of the DNS protocol (in RFC 4033, 4034, 4035, 6840, and related… CVSS 3.1HIGH 7.5
  • TI-2021-07476 A second vulnerability in BIND's GSSAPI security policy negotiation can be targeted by a buffer overflow attack CVSS 3.1CRITICAL 9.8
  • TI-1999-00042 Command execution via shell metachars in INN daemon (innd) 1.5 using "newgroup" and… CVSS 3.1CRITICAL 9.8
  • TI-2023-27773 The Closest Encloser Proof aspect of the DNS protocol (in RFC 5155 when RFC 9276 guidance… CVSS 3.1HIGH 7.5
  • TI-2025-27240 Cache poisoning attacks with unsolicited RRs CVSS 3.1HIGH 8.6
See all 285 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences