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.

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Source ID Title
Github GHSA Github GHSA GHSA-mv8m-v9v6-5f94 kas Persistently Disables SSH Host Key Checking
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Wed, 26 Aug 2026 19:45:00 +0000

Type Values Removed Values Added
First Time appeared Siemens
Siemens kas
Vendors & Products Siemens
Siemens kas

Wed, 26 Aug 2026 16:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Wed, 26 Aug 2026 14:30:00 +0000

Type Values Removed Values Added
Description 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.
Title kas: Persistent SSH Host Key Checking Disablement
Weaknesses CWE-295
References
Metrics cvssV3_1

{'score': 3.3, 'vector': 'CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:L/I:L/A:N'}


Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-08-26T15:36:30.207Z

Reserved: 2026-06-15T19:04:14.456Z

Link: CVE-2026-54548

cve-icon Vulnrichment

Updated: 2026-08-26T15:34:51.643Z

cve-icon NVD

Status : Received

Published: 2026-08-26T15:16:49.070

Modified: 2026-08-26T16:16:27.387

Link: CVE-2026-54548

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-08-26T19:30:05Z

Weaknesses