CVE-2026-54548

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 v3 3.3 LOW

3.3^/10

CVSS v3 : LOW

Vector :

Exploitability : 0.8 / Impact : 2.5

Attack Vector LOCAL

Attack Complexity HIGH

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/siemens/kas/commit/1c1e861c9f241ce082b86bef6bedc7da9b676294
https://github.com/siemens/kas/releases/tag/5.4
https://github.com/siemens/kas/security/advisories/GHSA-mv8m-v9v6-5f94

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-26 15:16

Updated : 2026-09-09 21:09

NVD link : CVE-2026-54548

Mitre link : CVE-2026-54548

CVE.ORG link : CVE-2026-54548

JSON object : View

Products Affected

No product.

CWE

CWE-295

Improper Certificate Validation

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