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CVE-2026-54478

CVE-2026-54478 · DNS Cookie bypass when combined with proxy-protocol use

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

In NLnet Labs Unbound 1.18.0 up to and including 1.25.1, when Unbound listens on a 'proxy-protocol-port' interface with 'answer-cookie: yes', the RFC 9018 server-cookie SipHash is computed over the proxy's wire address instead of the PROXYv2-declared client. One server cookie obtained through a given proxy node therefore validates for every PROXYv2-declared source behind that node. On a UDP+proxy-protocol front, an off-path attacker can harvest one cookie with a single legitimate query, then replay it under any spoofed source and pass DNS Cookie checks that were deployed to defeat this in the first place.

CVSS 3.7 · Low · EPSS 0.2% · Fix available

Published
Updated

Stack: system

Affected products and versions

  • unbound

    Versions
    • ≥ 1.18.0, < 1.25.2: Affected (semver)

    Update to 1.25.2

  • unbound Debian:12

    Versions
    • 1.17.1-2
    • 1.17.1-2+deb12u1
    • 1.17.1-2+deb12u2
    • 1.17.1-2+deb12u3
    • 1.17.1-2+deb12u4
    • 1.17.1-2+loong64
    • 1.18.0-1
    • 1.18.0-2
    • 1.19.1-1
    • 1.19.2-1
    • 1.20.0-1
    • 1.21.1-1
    • 1.22.0-1
    • 1.22.0-2
    • 1.23.1-1
    • 1.24.0-1
    • 1.24.0-2
    • 1.24.1-1
    • 1.24.1-2
    • 1.24.2-1
    • 1.25.0-1
    • 1.25.1-1
    • 1.25.2-1
    • 1.26.0-1
    • 1.26.0-2
    • 1.26.1-1
    • 1.26.2-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • unbound Debian:13

    Versions
    • 1.22.0-2
    • 1.22.0-2+deb13u1
    • 1.22.0-2+deb13u2
    • 1.22.0-2+deb13u3
    • 1.23.1-1
    • 1.24.0-1
    • 1.24.0-2
    • 1.24.1-1
    • 1.24.1-2
    • 1.24.2-1
    • 1.25.0-1
    • 1.25.1-1
    • 1.25.2-1
    • 1.26.0-1
    • 1.26.0-2
    Affected ranges
    • ECOSYSTEM: < 1.26.1-0+deb13u1

    Update to 1.26.1-0+deb13u1

  • unbound Debian:14

    Versions
    • 1.22.0-2
    • 1.23.1-1
    • 1.24.0-1
    • 1.24.0-2
    • 1.24.1-1
    • 1.24.1-2
    • 1.24.2-1
    • 1.25.0-1
    • 1.25.1-1
    Affected ranges
    • ECOSYSTEM: < 1.25.2-1

    Update to 1.25.2-1

  • unbound Ubuntu:Pro:14.04:LTS

    Versions
    • 1.4.20-1
    • 1.4.21-1
    • 1.4.21-1ubuntu1
    • 1.4.21-1ubuntu2
    • 1.4.22-1ubuntu1
    • 1.4.22-1ubuntu2
    • 1.4.22-1ubuntu3
    • 1.4.22-1ubuntu4
    • 1.4.22-1ubuntu4.14.04.1
    • 1.4.22-1ubuntu4.14.04.2
    • 1.4.22-1ubuntu4.14.04.3
    • 1.4.22-1ubuntu4.14.04.3+esm1
    • 1.4.22-1ubuntu4.14.04.3+esm2
    • 1.4.22-1ubuntu4.14.04.3+esm3
    • 1.4.22-1ubuntu4.14.04.3+esm4
    • 1.4.22-1ubuntu4.14.04.3+esm5
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • unbound Ubuntu:Pro:16.04:LTS

    Versions
    • 1.4.22-1ubuntu6
    • 1.5.7-1ubuntu1
    • 1.5.7-1ubuntu2
    • 1.5.8-1ubuntu1
    • 1.5.8-1ubuntu1.1
    • 1.5.8-1ubuntu1.1+esm1
    • 1.5.8-1ubuntu1.1+esm2
    • 1.5.8-1ubuntu1.1+esm3
    • 1.5.8-1ubuntu1.1+esm4
    • 1.5.8-1ubuntu1.1+esm5
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • unbound Ubuntu:Pro:18.04:LTS

    Versions
    • 1.6.5-1
    • 1.6.7-1
    • 1.6.7-1build1
    • 1.6.7-1ubuntu1
    • 1.6.7-1ubuntu2
    • 1.6.7-1ubuntu2.1
    • 1.6.7-1ubuntu2.2
    • 1.6.7-1ubuntu2.3
    • 1.6.7-1ubuntu2.4
    • 1.6.7-1ubuntu2.5
    • 1.6.7-1ubuntu2.6
    • 1.6.7-1ubuntu2.6+esm2
    • 1.6.7-1ubuntu2.6+esm3
    • 1.6.7-1ubuntu2.6+esm4
    • 1.6.7-1ubuntu2.6+esm5
    • 1.6.7-1ubuntu2.6+esm6
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • unbound Ubuntu:Pro:20.04:LTS

    Versions
    • 1.9.0-2ubuntu1
    • 1.9.0-2ubuntu2
    • 1.9.4-2
    • 1.9.4-2ubuntu1
    • 1.9.4-2ubuntu1.1
    • 1.9.4-2ubuntu1.2
    • 1.9.4-2ubuntu1.3
    • 1.9.4-2ubuntu1.4
    • 1.9.4-2ubuntu1.5
    • 1.9.4-2ubuntu1.6
    • 1.9.4-2ubuntu1.8
    • 1.9.4-2ubuntu1.9
    • 1.9.4-2ubuntu1.11
    • 1.9.4-2ubuntu1.11+esm1
    • 1.9.4-2ubuntu1.11+esm2
    • 1.9.4-2ubuntu1.11+esm3
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • unbound Ubuntu:22.04:LTS

    Versions
    • 1.13.1-1ubuntu1
    • 1.13.1-1ubuntu3
    • 1.13.1-1ubuntu5
    • 1.13.1-1ubuntu5.1
    • 1.13.1-1ubuntu5.2
    • 1.13.1-1ubuntu5.3
    • 1.13.1-1ubuntu5.4
    • 1.13.1-1ubuntu5.5
    • 1.13.1-1ubuntu5.7
    • 1.13.1-1ubuntu5.8
    • 1.13.1-1ubuntu5.10
    • 1.13.1-1ubuntu5.11
    • 1.13.1-1ubuntu5.12
    • 1.13.1-1ubuntu5.13
    • 1.13.1-1ubuntu5.14
    • 1.13.1-1ubuntu5.15
    • 1.13.1-1ubuntu5.16
    • 1.13.1-1ubuntu5.17
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • unbound Ubuntu:24.04:LTS

    Versions
    • 1.17.1-2
    • 1.18.0-2ubuntu1
    • 1.18.0-2ubuntu2
    • 1.19.1-1ubuntu1
    • 1.19.2-1ubuntu1
    • 1.19.2-1ubuntu3
    • 1.19.2-1ubuntu3.1
    • 1.19.2-1ubuntu3.2
    • 1.19.2-1ubuntu3.3
    • 1.19.2-1ubuntu3.4
    • 1.19.2-1ubuntu3.5
    • 1.19.2-1ubuntu3.6
    • 1.19.2-1ubuntu3.7
    • 1.19.2-1ubuntu3.8
    • 1.19.2-1ubuntu3.9
    • 1.19.2-1ubuntu3.10
    • 1.19.2-1ubuntu3.12
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • unbound Ubuntu:26.10

    Versions
    • 1.24.2-1ubuntu2
    • 1.25.1-1ubuntu1
    • 1.25.1-1ubuntu3
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • unbound Ubuntu:26.04:LTS

    Versions
    • 1.22.0-2ubuntu2
    • 1.22.0-2ubuntu4
    • 1.24.2-1ubuntu1
    • 1.24.2-1ubuntu2
    • 1.24.2-1ubuntu2.1
    • 1.24.2-1ubuntu2.2
    • 1.24.2-1ubuntu2.3
    • 1.24.2-1ubuntu2.4
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

Original sources

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