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CVE-2026-18103

CVE-2026-18103 · Dhcp-server: dhcp-server: persistent denial of service due to buffer overflow via omapi

This page contains facts from public vulnerability sources. Check the original advisory before updating.

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.

CVSS 4.9 · Medium · EPSS 0.7%

Published
Updated

Stack: system

Affected products and versions

  • red hat enterprise linux 6

    No fix published

  • red hat enterprise linux 7

    No fix published

  • red hat enterprise linux 8

    No fix published

  • red hat enterprise linux 9

    No fix published

  • isc-dhcp Debian:12

    Versions
    • 4.4.3-P1-2
    • 4.4.3-P1-3
    • 4.4.3-P1-4
    • 4.4.3-P1-5
    • 4.4.3-P1-5~exp1
    • 4.4.3-P1-5~exp2
    • 4.4.3-P1-6
    • 4.4.3-P1-7
    • 4.4.3-P1-8
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • isc-dhcp Debian:13

    Versions
    • 4.4.3-P1-8
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • isc-dhcp Ubuntu:Pro:14.04:LTS

    Versions
    • 4.2.4-7ubuntu8
    • 4.2.4-7ubuntu9
    • 4.2.4-7ubuntu10
    • 4.2.4-7ubuntu11
    • 4.2.4-7ubuntu12
    • 4.2.4-7ubuntu12.1
    • 4.2.4-7ubuntu12.2
    • 4.2.4-7ubuntu12.3
    • 4.2.4-7ubuntu12.4
    • 4.2.4-7ubuntu12.5
    • 4.2.4-7ubuntu12.6
    • 4.2.4-7ubuntu12.7
    • 4.2.4-7ubuntu12.8
    • 4.2.4-7ubuntu12.9
    • 4.2.4-7ubuntu12.10
    • 4.2.4-7ubuntu12.12
    • 4.2.4-7ubuntu12.13
    • 4.2.4-7ubuntu12.13+esm1
    • 4.2.4-7ubuntu12.13+esm2
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • isc-dhcp Ubuntu:Pro:16.04:LTS

    Versions
    • 4.3.1-5ubuntu3
    • 4.3.1-5ubuntu4
    • 4.3.1-5ubuntu5
    • 4.3.3-5ubuntu1
    • 4.3.3-5ubuntu2
    • 4.3.3-5ubuntu4
    • 4.3.3-5ubuntu5
    • 4.3.3-5ubuntu7
    • 4.3.3-5ubuntu8
    • 4.3.3-5ubuntu9
    • 4.3.3-5ubuntu10
    • 4.3.3-5ubuntu11
    • 4.3.3-5ubuntu12
    • 4.3.3-5ubuntu12.1
    • 4.3.3-5ubuntu12.3
    • 4.3.3-5ubuntu12.4
    • 4.3.3-5ubuntu12.6
    • 4.3.3-5ubuntu12.7
    • 4.3.3-5ubuntu12.9
    • 4.3.3-5ubuntu12.10
    • 4.3.3-5ubuntu12.10+esm1
    • 4.3.3-5ubuntu12.10+esm2
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • isc-dhcp Ubuntu:18.04:LTS

    Versions
    • 4.3.5-3ubuntu2
    • 4.3.5-3ubuntu3
    • 4.3.5-3ubuntu4
    • 4.3.5-3ubuntu5
    • 4.3.5-3ubuntu6
    • 4.3.5-3ubuntu7
    • 4.3.5-3ubuntu7.1
    • 4.3.5-3ubuntu7.2
    • 4.3.5-3ubuntu7.3
    • 4.3.5-3ubuntu7.4
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • isc-dhcp Ubuntu:20.04:LTS

    Versions
    • 4.4.1-2ubuntu5
    • 4.4.1-2ubuntu6
    • 4.4.1-2.1ubuntu1
    • 4.4.1-2.1ubuntu2
    • 4.4.1-2.1ubuntu3
    • 4.4.1-2.1ubuntu4
    • 4.4.1-2.1ubuntu5
    • 4.4.1-2.1ubuntu5.20.04.1
    • 4.4.1-2.1ubuntu5.20.04.2
    • 4.4.1-2.1ubuntu5.20.04.3
    • 4.4.1-2.1ubuntu5.20.04.4
    • 4.4.1-2.1ubuntu5.20.04.5
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • isc-dhcp Ubuntu:22.04:LTS

    Versions
    • 4.4.1-2.3ubuntu1
    • 4.4.1-2.3ubuntu2
    • 4.4.1-2.3ubuntu2.1
    • 4.4.1-2.3ubuntu2.2
    • 4.4.1-2.3ubuntu2.3
    • 4.4.1-2.3ubuntu2.4
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • isc-dhcp Ubuntu:24.04:LTS

    Versions
    • 4.4.3-P1-2ubuntu5
    • 4.4.3-P1-4ubuntu1
    • 4.4.3-P1-4ubuntu2
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • isc-dhcp Ubuntu:26.04:LTS

    Versions
    • 4.4.3-P1-4ubuntu2
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

Original sources

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