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CVE-2026-54548

CVE-2026-54548 · kas: Persistent SSH Host Key Checking Disablement

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

kas is a setup tool for bitbake based projects. Prior to 5.4, internal SSH key setup triggered by SSH_PRIVATE_KEY or SSH_PRIVATE_KEY_FILE creates ~/.ssh/config when no user-specific SSH configuration exists and adds a global Host * rule containing StrictHostKeyChecking no. In kas/libcmds.py, ssh_no_host_key_check() runs without checking ctx.managed_env, so the setting persists after kas exits and affects future SSH sessions by the same local user, extending beyond the intended short-lived continuous integration environment. A later SSH connection can therefore accept an attacker-controlled host key without verification, increasing the risk of a man-in-the-middle attack that compromises session confidentiality or integrity. This issue is fixed in version 5.4.

CVSS 3.3 · Low · EPSS 0.1% · Fix available

Published
Updated

Stack: system · python

Affected products and versions

  • kas

    Versions
    • < 5.4: Affected

    No fix published

  • kas Debian:12

    Versions
    • 3.1-2
    • 3.2.3-1
    • 4.0-1
    • 4.3-1
    • 4.3.2-1
    • 4.4-1
    • 4.4-2
    • 4.5-1
    • 4.5-2
    • 4.6-1
    • 4.7-1
    • 4.8.1-1
    • 4.8.1-2
    • 4.8.2-1
    • 5.0-1
    • 5.1-1
    • 5.2-1
    • 5.3-1
    • 5.4-1
    • 5.5-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • kas Debian:13

    Versions
    • 4.8.1-2
    • 4.8.2-1
    • 5.0-1
    • 5.1-1
    • 5.2-1
    • 5.3-1
    • 5.4-1
    • 5.5-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • kas Debian:14

    Versions
    • 4.8.1-2
    • 4.8.2-1
    • 5.0-1
    • 5.1-1
    • 5.2-1
    • 5.3-1
    Affected ranges
    • ECOSYSTEM: < 5.4-1

    Update to 5.4-1

  • kas PyPI

    Versions
    • 0.11.0
    • 0.13.0
    • 0.14.0
    • 0.15.0
    • 0.16.1
    • 0.17.0
    • 0.18.0
    • 0.19.0
    • 0.20.0
    • 0.20.1
    • 1.0
    • 1.1
    • 2.0
    • 2.1
    • 2.1.1
    • 2.2
    • 2.3
    • 2.3.1
    • 2.3.2
    • 2.3.3
    • 2.4
    • 2.5
    • 2.6
    • 2.6.1
    • 2.6.2
    • 2.6.3
    • 3.0
    • 3.0.1
    • 3.0.2
    • 3.1
    • 3.2
    • 3.2.1
    • 3.2.2
    • 3.2.3
    • 3.3
    • 4.0
    • 4.1
    • 4.2
    • 4.3
    • 4.3.1
    • 4.3.2
    • 4.4
    • 4.5
    • 4.6
    • 4.7
    • 4.8
    • 4.8.1
    • 4.8.2
    • 5.0
    • 5.1
    • 5.2
    • 5.3
    Affected ranges
    • ECOSYSTEM: < 5.4

    Update to 5.4

  • kas Ubuntu:22.04:LTS

    Versions
    • 2.3.3-2
    • 2.5-1
    • 2.6.3-2
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • kas Ubuntu:24.04:LTS

    Versions
    • 4.0-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • kas Ubuntu:25.10

    Versions
    • 4.7-1
    • 4.8.1-1
    • 4.8.1-2
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • kas Ubuntu:26.10

    Versions
    • 5.1-1
    • 5.2-1
    • 5.4-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • kas Ubuntu:26.04:LTS

    Versions
    • 4.8.1-2
    • 5.0-1
    • 5.1-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

Original sources

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