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CVE-2026-40012

CVE-2026-40012 · Information about ECS zero scoped answers might leak to clients that use a specific ECS

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

ECS zero scoped answers are stored in the packet cache while they should not. This impacts only configurations that have ECS enabled;

CVSS 5.3 · Medium · EPSS 0.5% · Fix available

Published
Updated

Stack: system

Affected products and versions

  • recursor

    Versions
    • ≥ 5.2.0, < 5.2.11: Affected (semver)
    • ≥ 5.3.0, < 5.3.8: Affected (semver)
    • ≥ 5.4.0, < 5.4.3: Affected (semver)

    Update to 5.2.11; Update to 5.3.8; Update to 5.4.3

  • pdns-recursor Debian:12

    Versions
    • 4.8.4-1
    • 4.8.6-1
    • 4.8.7-1
    • 4.8.8-1
    • 4.8.8-1+deb12u1
    • 4.9.0-1
    • 4.9.0-2
    • 4.9.1-1
    • 4.9.1-2
    • 4.9.1-3
    • 4.9.1-4
    • 4.9.2-1
    • 4.9.2-2
    • 4.9.3-1
    • 4.9.4-1
    • 4.9.5-1
    • 5.0.5-1
    • 5.0.7-1
    • 5.0.7-2
    • 5.0.9-1
    • 5.1.3-1
    • 5.1.3-2
    • 5.2.0-1
    • 5.2.0-2
    • 5.2.0-3
    • 5.2.0-4
    • 5.2.0-5
    • 5.2.1-1
    • 5.2.2-1
    • 5.2.2-2
    • 5.2.4-1
    • 5.2.4-2
    • 5.2.5-1
    • 5.3.0-1
    • 5.3.0-2
    • 5.3.0-3
    • 5.3.0-4
    • 5.3.0-5
    • 5.3.1-1
    • 5.3.3-1
    • 5.3.4-1
    • 5.3.4-2
    • 5.3.5-1
    • 5.4.0-1
    • 5.4.1-1
    • 5.4.1-2
    • 5.4.2-1
    • 5.4.2-2
    • 5.4.3-1
    • 5.4.4-1
    • 5.4.5-1
    • 5.4.6-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • pdns-recursor Debian:13

    Versions
    • 5.2.4-2
    • 5.2.4-2+deb13u1
    • 5.2.5-1
    • 5.2.6-0+deb13u1
    • 5.2.7-0+deb13u1
    • 5.2.8-0+deb13u1
    • 5.2.9-0+deb13u1
    Affected ranges
    • ECOSYSTEM: < 5.2.11-0+deb13u1

    Update to 5.2.11-0+deb13u1

  • pdns-recursor Debian:14

    Versions
    • 5.2.4-2
    • 5.2.5-1
    • 5.3.0-1
    • 5.3.0-2
    • 5.3.0-3
    • 5.3.0-4
    • 5.3.0-5
    • 5.3.1-1
    • 5.3.3-1
    • 5.3.4-1
    • 5.3.4-2
    • 5.3.5-1
    • 5.4.0-1
    • 5.4.1-1
    • 5.4.1-2
    • 5.4.2-1
    • 5.4.2-2
    Affected ranges
    • ECOSYSTEM: < 5.4.3-1

    Update to 5.4.3-1

  • pdns-recursor Ubuntu:Pro:16.04:LTS

    Versions
    • 3.7.3-1
    • 4.0.0~alpha1-1
    • 4.0.0~alpha1-2
    • 4.0.0~alpha2-2
    • 4.0.0~alpha2-2ubuntu0.1
    • 4.0.0~alpha2-2ubuntu0.1+esm1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • pdns-recursor Ubuntu:Pro:18.04:LTS

    Versions
    • 4.0.6-1
    • 4.0.6-1build1
    • 4.0.7-1
    • 4.1.1-1
    • 4.1.1-1build1
    • 4.1.1-2
    • 4.1.1-2ubuntu0.1~esm1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • pdns-recursor Ubuntu:Pro:20.04:LTS

    Versions
    • 4.2.0-6
    • 4.2.1-1
    • 4.2.1-1build1
    • 4.2.1-1build2
    • 4.2.1-1ubuntu0.1~esm1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • pdns-recursor Ubuntu:Pro:22.04:LTS

    Versions
    • 4.4.2-3
    • 4.6.0-1ubuntu1
    • 4.6.0-1ubuntu1+esm1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • pdns-recursor Ubuntu:24.04:LTS

    Versions
    • 4.9.0-2
    • 4.9.1-4
    • 4.9.2-1
    • 4.9.2-1build1
    • 4.9.2-2
    • 4.9.3-1
    • 4.9.3-1build2
    • 4.9.3-1build3
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • pdns-recursor Ubuntu:25.10

    Versions
    • 5.2.0-5
    • 5.2.2-1
    • 5.2.2-2
    • 5.2.4-2
    • 5.2.4-2build2
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • pdns-recursor Ubuntu:26.10

    Versions
    • 5.3.5-1
    • 5.4.3-1
    • 5.4.5-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • pdns-recursor Ubuntu:26.04:LTS

    Versions
    • 5.2.4-2build2
    • 5.3.1-1
    • 5.3.3-1
    • 5.3.4-1
    • 5.3.4-1build1
    • 5.3.4-2
    • 5.3.5-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

Original sources

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