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CVE-2026-87121

CVE-2026-87121 · Out-of-bounds write in lwIP TCP/IP Stack MQTT Client Application

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

lwIP TCP/IP Stack MQTT is vulnerable to an out-of-bounds write, which may allow an attacker to gain full code execution on the device.

CVSS 9.3 · Critical · EPSS 0.5% · Fix available

Published
Updated

Stack: system

Affected products and versions

  • tcp/ip stack mqtt

    Versions
    • ≥ 2.0.1, ≤ 2.2.1: Affected (custom)

    No fix published

  • lwip Debian:12

    Versions
    • 2.1.3+dfsg1-2
    • 2.1.3+dfsg1-3
    • 2.1.3+dfsg1-4
    • 2.2.0+dfsg1-1
    • 2.2.0+dfsg1-2
    • 2.2.0+dfsg1-3
    • 2.2.0+dfsg1-4
    • 2.2.0+dfsg1-5
    • 2.2.0+dfsg1-6
    • 2.2.0+dfsg1-6.1
    • 2.2.0+dfsg1-6.1~exp1
    • 2.2.0+dfsg1-7
    • 2.2.0+dfsg1-8
    • 2.2.0+dfsg1-9
    • 2.2.1+dfsg1-1
    • 2.2.1+dfsg1-2
    • 2.2.1+dfsg1-3
    • 2.2.1+dfsg1-4
    • 2.2.1+dfsg1-5
    • 2.2.1+dfsg1-6
    • 2.2.1+dfsg1-7
    • 2.2.1+dfsg1-8
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • lwip Debian:13

    Versions
    • 2.2.1+dfsg1-1
    • 2.2.1+dfsg1-1+deb13u1
    • 2.2.1+dfsg1-2
    • 2.2.1+dfsg1-3
    • 2.2.1+dfsg1-4
    • 2.2.1+dfsg1-5
    • 2.2.1+dfsg1-6
    • 2.2.1+dfsg1-7
    • 2.2.1+dfsg1-8
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • lwip Debian:14

    Versions
    • 2.2.1+dfsg1-1
    • 2.2.1+dfsg1-2
    • 2.2.1+dfsg1-3
    • 2.2.1+dfsg1-4
    • 2.2.1+dfsg1-5
    • 2.2.1+dfsg1-6
    • 2.2.1+dfsg1-7
    Affected ranges
    • ECOSYSTEM: < 2.2.1+dfsg1-8

    Update to 2.2.1+dfsg1-8

  • lwip Ubuntu:Pro:20.04:LTS

    Versions
    • 2.1.2-3
    • 2.1.2-5.1
    • 2.1.2+dfsg1-1
    • 2.1.2+dfsg1-4
    • 2.1.2+dfsg1-4ubuntu0.1~esm1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • lwip Ubuntu:Pro:22.04:LTS

    Versions
    • 2.1.2+dfsg1-8
    • 2.1.2+dfsg1-9
    • 2.1.3+dfsg1-1
    • 2.1.3+dfsg1-1ubuntu0.1~esm1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • lwip Ubuntu:Pro:24.04:LTS

    Versions
    • 2.1.3+dfsg1-2
    • 2.1.3+dfsg1-4
    • 2.2.0+dfsg1-2
    • 2.2.0+dfsg1-3
    • 2.2.0+dfsg1-4
    • 2.2.0+dfsg1-5
    • 2.2.0+dfsg1-6
    • 2.2.0+dfsg1-6.1
    • 2.2.0+dfsg1-6.1build1
    • 2.2.0+dfsg1-6.1build2
    • 2.2.0+dfsg1-6.1ubuntu0.1~esm1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • lwip Ubuntu:26.10

    Versions
    • 2.2.1+dfsg1-4
    • 2.2.1+dfsg1-5
    • 2.2.1+dfsg1-7
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • lwip Ubuntu:Pro:26.04:LTS

    Versions
    • 2.2.1+dfsg1-2
    • 2.2.1+dfsg1-3
    • 2.2.1+dfsg1-4
    • 2.2.1+dfsg1-4ubuntu0.1~esm1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

Original sources

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