CVE catalog

CVE-2026-18103

A flaw was found in dhcp-server. A remote attacker with network access to the OMAPI (Open Management Application Programming Interface) port, especially if not secured with TSIG (Transaction Signature

[CVE catalog]

Severity
Medium · CVSS 4.9CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
Published
Source
[NVD] · [CVE record]
EPSS
0.71% · Oct 25, 2026

A flaw was found in dhcp-server. A remote attacker with network access to the OMAPI (Open Management Application Programming Interface) port, especially if not secured with TSIG (Transaction Signature) key authentication, could send a specially crafted lease creation request. This request, containing an overly long InfiniBand MAC address, triggers a buffer overflow in the `print_hw_addr()` function. Successful exploitation leads to a persistent denial of service (DoS), causing the `dhcpd` service to crash and preventing it from restarting without manual intervention.

Vulnerable and fixed packages

Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.

DistributionPackageReleaseVersionStatus
Debianisc-dhcptrixie4.4.3-P1-8vulnerable
Debianisc-dhcpbookworm4.4.3-P1-2vulnerable
Ubuntuisc-dhcppro4.3.1-5ubuntu3vulnerable
Ubuntuisc-dhcppro4.3.1-5ubuntu4vulnerable
Ubuntuisc-dhcppro4.3.1-5ubuntu5vulnerable
Ubuntuisc-dhcppro4.3.3-5ubuntu1vulnerable
Ubuntuisc-dhcppro4.3.3-5ubuntu2vulnerable
Ubuntuisc-dhcppro4.3.3-5ubuntu4vulnerable
Ubuntuisc-dhcppro4.3.3-5ubuntu5vulnerable
Ubuntuisc-dhcppro4.3.3-5ubuntu7vulnerable
Ubuntuisc-dhcppro4.3.3-5ubuntu8vulnerable
Ubuntuisc-dhcppro4.3.3-5ubuntu9vulnerable
Ubuntuisc-dhcppro4.3.3-5ubuntu10vulnerable
Ubuntuisc-dhcppro4.3.3-5ubuntu11vulnerable
Ubuntuisc-dhcppro4.3.3-5ubuntu12vulnerable
Ubuntuisc-dhcppro4.3.3-5ubuntu12.1vulnerable
Ubuntuisc-dhcppro4.3.3-5ubuntu12.3vulnerable
Ubuntuisc-dhcppro4.3.3-5ubuntu12.4vulnerable
Ubuntuisc-dhcppro4.3.3-5ubuntu12.6vulnerable
Ubuntuisc-dhcppro4.3.3-5ubuntu12.7vulnerable
Ubuntuisc-dhcppro4.3.3-5ubuntu12.9vulnerable
Ubuntuisc-dhcppro4.3.3-5ubuntu12.10vulnerable
Ubuntuisc-dhcppro4.3.3-5ubuntu12.10+esm1vulnerable
Ubuntuisc-dhcppro4.3.3-5ubuntu12.10+esm2vulnerable
Ubuntuisc-dhcp18.044.3.5-3ubuntu2vulnerable
Ubuntuisc-dhcp18.044.3.5-3ubuntu3vulnerable
Ubuntuisc-dhcp18.044.3.5-3ubuntu4vulnerable
Ubuntuisc-dhcp18.044.3.5-3ubuntu5vulnerable
Ubuntuisc-dhcp18.044.3.5-3ubuntu6vulnerable
Ubuntuisc-dhcp18.044.3.5-3ubuntu7vulnerable
Ubuntuisc-dhcp18.044.3.5-3ubuntu7.1vulnerable
Ubuntuisc-dhcp18.044.3.5-3ubuntu7.2vulnerable
Ubuntuisc-dhcp18.044.3.5-3ubuntu7.3vulnerable
Ubuntuisc-dhcp18.044.3.5-3ubuntu7.4vulnerable
Ubuntuisc-dhcp20.044.4.1-2ubuntu5vulnerable
Ubuntuisc-dhcp20.044.4.1-2ubuntu6vulnerable
Ubuntuisc-dhcp20.044.4.1-2.1ubuntu1vulnerable
Ubuntuisc-dhcp20.044.4.1-2.1ubuntu2vulnerable
Ubuntuisc-dhcp20.044.4.1-2.1ubuntu3vulnerable
Ubuntuisc-dhcp20.044.4.1-2.1ubuntu4vulnerable
Ubuntuisc-dhcp20.044.4.1-2.1ubuntu5vulnerable
Ubuntuisc-dhcp20.044.4.1-2.1ubuntu5.20.04.1vulnerable
Ubuntuisc-dhcp20.044.4.1-2.1ubuntu5.20.04.2vulnerable
Ubuntuisc-dhcp20.044.4.1-2.1ubuntu5.20.04.3vulnerable
Ubuntuisc-dhcp20.044.4.1-2.1ubuntu5.20.04.4vulnerable
Ubuntuisc-dhcp20.044.4.1-2.1ubuntu5.20.04.5vulnerable
Ubuntuisc-dhcp22.044.4.1-2.3ubuntu1vulnerable
Ubuntuisc-dhcp22.044.4.1-2.3ubuntu2vulnerable
Ubuntuisc-dhcp22.044.4.1-2.3ubuntu2.1vulnerable
Ubuntuisc-dhcp22.044.4.1-2.3ubuntu2.2vulnerable
Ubuntuisc-dhcp22.044.4.1-2.3ubuntu2.3vulnerable
Ubuntuisc-dhcp22.044.4.1-2.3ubuntu2.4vulnerable
Ubuntuisc-dhcp24.044.4.3-P1-2ubuntu5vulnerable
Ubuntuisc-dhcp24.044.4.3-P1-4ubuntu1vulnerable
Ubuntuisc-dhcp24.044.4.3-P1-4ubuntu2vulnerable
Ubuntuisc-dhcp26.044.4.3-P1-4ubuntu2vulnerable

Fixed-version evidence

DistributionPackageTypeReleaseFixed versionUrgencyOriginBugs
Debianisc-dhcpsourcetrixie(unfixed)not yet assignedNot reportedNot reported
Debianisc-dhcpsourcebookworm(unfixed)not yet assignedNot reportedNot reported

Notes

[trixie] isc-dhcp: ISC DHCP not covered by security support in Trixie [bookworm] isc-dhcp: ISC DHCP not covered by security support in Trixie

OpenFactory catalog packages

[Debian 12 (Bookworm)]

  • [isc-dhcp-client]Affected

    Source package: [isc-dhcp]

    Details (2)

    • 4.4.3-P1-2 · amd64 · bookworm

      Affected

      nvd · isc-dhcp · debian · bookworm; nvd · isc-dhcp · debian · 12

    • 4.4.3-P1-2 · arm64 · bookworm

      Affected

      nvd · isc-dhcp · debian · bookworm; nvd · isc-dhcp · debian · 12

  • [isc-dhcp-client-ddns]Affected

    Source package: [isc-dhcp]

    Details (2)

    • 4.4.3-P1-2 · amd64 · bookworm

      Affected

      nvd · isc-dhcp · debian · bookworm; nvd · isc-dhcp · debian · 12

    • 4.4.3-P1-2 · arm64 · bookworm

      Affected

      nvd · isc-dhcp · debian · bookworm; nvd · isc-dhcp · debian · 12

  • [isc-dhcp-common]Affected

    Source package: [isc-dhcp]

    Details (2)

    • 4.4.3-P1-2 · amd64 · bookworm

      Affected

      nvd · isc-dhcp · debian · bookworm; nvd · isc-dhcp · debian · 12

    • 4.4.3-P1-2 · arm64 · bookworm

      Affected

      nvd · isc-dhcp · debian · bookworm; nvd · isc-dhcp · debian · 12

  • [isc-dhcp-dev]Affected

    Source package: [isc-dhcp]

    Details (2)

    • 4.4.3-P1-2 · amd64 · bookworm

      Affected

      nvd · isc-dhcp · debian · bookworm; nvd · isc-dhcp · debian · 12

    • 4.4.3-P1-2 · arm64 · bookworm

      Affected

      nvd · isc-dhcp · debian · bookworm; nvd · isc-dhcp · debian · 12

  • [isc-dhcp-relay]Affected

    Source package: [isc-dhcp]

    Details (2)

    • 4.4.3-P1-2 · amd64 · bookworm

      Affected

      nvd · isc-dhcp · debian · bookworm; nvd · isc-dhcp · debian · 12

    • 4.4.3-P1-2 · arm64 · bookworm

      Affected

      nvd · isc-dhcp · debian · bookworm; nvd · isc-dhcp · debian · 12

  • [isc-dhcp-server]Affected

    Source package: [isc-dhcp]

    Details (2)

    • 4.4.3-P1-2 · amd64 · bookworm

      Affected

      nvd · isc-dhcp · debian · bookworm; nvd · isc-dhcp · debian · 12

    • 4.4.3-P1-2 · arm64 · bookworm

      Affected

      nvd · isc-dhcp · debian · bookworm; nvd · isc-dhcp · debian · 12

  • [isc-dhcp-server-ldap]Affected

    Source package: [isc-dhcp]

    Details (2)

    • 4.4.3-P1-2 · amd64 · bookworm

      Affected

      nvd · isc-dhcp · debian · bookworm; nvd · isc-dhcp · debian · 12

    • 4.4.3-P1-2 · arm64 · bookworm

      Affected

      nvd · isc-dhcp · debian · bookworm; nvd · isc-dhcp · debian · 12

[Debian 13 (Trixie)]

  • [isc-dhcp-client]Affected

    Source package: [isc-dhcp]

    Details (2)

    • 4.4.3-P1-8 · amd64 · trixie

      Affected

      nvd · isc-dhcp · debian · 13

    • 4.4.3-P1-8 · arm64 · trixie

      Affected

      nvd · isc-dhcp · debian · 13

  • [isc-dhcp-client-ddns]Affected

    Source package: [isc-dhcp]

    Details (2)

    • 4.4.3-P1-8 · amd64 · trixie

      Affected

      nvd · isc-dhcp · debian · 13

    • 4.4.3-P1-8 · arm64 · trixie

      Affected

      nvd · isc-dhcp · debian · 13

  • [isc-dhcp-common]Affected

    Source package: [isc-dhcp]

    Details (2)

    • 4.4.3-P1-8 · amd64 · trixie

      Affected

      nvd · isc-dhcp · debian · 13

    • 4.4.3-P1-8 · arm64 · trixie

      Affected

      nvd · isc-dhcp · debian · 13

  • [isc-dhcp-dev]Affected

    Source package: [isc-dhcp]

    Details (2)

    • 4.4.3-P1-8 · amd64 · trixie

      Affected

      nvd · isc-dhcp · debian · 13

    • 4.4.3-P1-8 · arm64 · trixie

      Affected

      nvd · isc-dhcp · debian · 13

  • [isc-dhcp-keama]Affected

    Source package: [isc-dhcp]

    Details (2)

    • 4.4.3-P1-8 · amd64 · trixie

      Affected

      nvd · isc-dhcp · debian · 13

    • 4.4.3-P1-8 · arm64 · trixie

      Affected

      nvd · isc-dhcp · debian · 13

  • [isc-dhcp-relay]Affected

    Source package: [isc-dhcp]

    Details (2)

    • 4.4.3-P1-8 · amd64 · trixie

      Affected

      nvd · isc-dhcp · debian · 13

    • 4.4.3-P1-8 · arm64 · trixie

      Affected

      nvd · isc-dhcp · debian · 13

  • [isc-dhcp-server]Affected

    Source package: [isc-dhcp]

    Details (2)

    • 4.4.3-P1-8 · amd64 · trixie

      Affected

      nvd · isc-dhcp · debian · 13

    • 4.4.3-P1-8 · arm64 · trixie

      Affected

      nvd · isc-dhcp · debian · 13

  • [isc-dhcp-server-ldap]Affected

    Source package: [isc-dhcp]

    Details (2)

    • 4.4.3-P1-8 · amd64 · trixie

      Affected

      nvd · isc-dhcp · debian · 13

    • 4.4.3-P1-8 · arm64 · trixie

      Affected

      nvd · isc-dhcp · debian · 13

Observed:

References

[Debian Security Tracker] · [FIRST EPSS] · [National Vulnerability Database (NVD)] · [OSV Package Vulnerability Database] · [Red Hat security advisories and VEX] · [SUSE security advisories and VEX]