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CVE-2026-18664

CVE-2026-18664 · Wrong interpretation of ACL ranges

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

When ranges are used for access control (i.e. of the form 1.2.3.4-1.2.3.25), because NSD wrongly compares the IP address with the range on little endian systems, IPs that were meant to be allowed may be denied, and, IPs that were meant to be denied access could be allowed. An IPv4 address is compared with IPv4 ranges as unsigned 32 bit numbers directly with the endianness of the host, but the values to compare are in network byte order (big-endian). With IPv6 addresses the comparison is done in 4 times a unsigned 32 bit number comparison, again with the endianness of the host where all values are actually in network bye order.

CVSS 8.2 · High · EPSS 0.3% · Fix available

Published
Updated

Stack: system

Affected products and versions

  • nsd

    Versions
    • ≥ 3.0.0, < 4.15.1: Affected (semver)

    Update to 4.15.1

  • nsd Debian:12

    Versions
    • 4.10.1-1
    • 4.10.1~rc2-1
    • 4.10.1~rc2-2
    • 4.11.0-1
    • 4.11.1-1
    • 4.12.0-1
    • 4.12.0-2
    • 4.13.0-1
    • 4.13.0-2
    • 4.13.0-3
    • 4.13.0-4
    • 4.13.0-5
    • 4.13.0-6
    • 4.14.0-1
    • 4.14.1-1
    • 4.14.2-1
    • 4.14.3-1
    • 4.15.0-1
    • 4.15.0~rc1-1
    • 4.15.1-1
    • 4.15.2-1
    • 4.6.1-1
    • 4.7.0-1
    • 4.8.0-1
    • 4.9.1-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • nsd Debian:13

    Versions
    • 4.12.0-1
    • 4.12.0-2
    • 4.13.0-1
    • 4.13.0-2
    • 4.13.0-3
    • 4.13.0-4
    • 4.13.0-5
    • 4.13.0-6
    • 4.14.0-1
    • 4.14.1-1
    • 4.14.2-1
    • 4.14.3-1
    • 4.15.0-1
    • 4.15.0~rc1-1
    • 4.15.1-1
    • 4.15.2-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • nsd Debian:14

    Versions
    • 4.12.0-1
    • 4.12.0-2
    • 4.13.0-1
    • 4.13.0-2
    • 4.13.0-3
    • 4.13.0-4
    • 4.13.0-5
    • 4.13.0-6
    • 4.14.0-1
    • 4.14.1-1
    • 4.14.2-1
    • 4.14.3-1
    • 4.15.0-1
    • 4.15.0~rc1-1
    Affected ranges
    • ECOSYSTEM: < 4.15.1-1

    Update to 4.15.1-1

  • nsd Ubuntu:Pro:16.04:LTS

    Versions
    • 4.1.2-1
    • 4.1.6-1
    • 4.1.7-1
    • 4.1.7-1ubuntu0.1~esm1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • nsd Ubuntu:Pro:18.04:LTS

    Versions
    • 4.1.16-1build1
    • 4.1.17-1
    • 4.1.17-1build1
    • 4.1.17-1ubuntu0.1~esm1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • nsd Ubuntu:Pro:20.04:LTS

    Versions
    • 4.1.26-1
    • 4.1.26-1build1
    • 4.1.26-1ubuntu0.1~esm1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • nsd Ubuntu:Pro:22.04:LTS

    Versions
    • 4.3.5-1
    • 4.3.7-1
    • 4.3.8-1
    • 4.3.8-1build1
    • 4.3.9-1
    • 4.3.9-1ubuntu0.1~esm1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • nsd Ubuntu:Pro:24.04:LTS

    Versions
    • 4.7.0-1
    • 4.8.0-1
    • 4.8.0-1build1
    • 4.8.0-1build3
    • 4.8.0-1ubuntu0.1~esm1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • nsd Ubuntu:26.10

    Versions
    • 4.14.0-1
    • 4.14.2-1
    • 4.14.3-1
    • 4.15.0-1
    • 4.15.0-1build1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • nsd Ubuntu:Pro:26.04:LTS

    Versions
    • 4.12.0-1
    • 4.13.0-6
    • 4.14.0-1
    • 4.14.0-1ubuntu0.1~esm1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

Original sources

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