{"id":"UBUNTU-CVE-2026-54548","details":"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.","modified":"2026-09-02T19:36:19.773129817Z","published":"2026-08-26T15:16:00Z","upstream":["CVE-2026-54548"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-54548"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-54548"},{"type":"REPORT","url":"https://github.com/siemens/kas/security/advisories/GHSA-mv8m-v9v6-5f94"}],"affected":[{"package":{"name":"kas","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/kas?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.3.3-2","2.5-1","2.6.3-2"],"ecosystem_specific":{"binaries":[{"binary_name":"kas","binary_version":"2.6.3-2"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-54548.json"}},{"package":{"name":"kas","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/kas?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["4.0-1"],"ecosystem_specific":{"binaries":[{"binary_version":"4.0-1","binary_name":"kas"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-54548.json"}},{"package":{"name":"kas","ecosystem":"Ubuntu:25.10","purl":"pkg:deb/ubuntu/kas?arch=source&distro=questing"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["4.7-1","4.8.1-1","4.8.1-2"],"ecosystem_specific":{"binaries":[{"binary_name":"kas","binary_version":"4.8.1-2"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-54548.json"}},{"package":{"name":"kas","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/kas?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["4.8.1-2","5.0-1","5.1-1"],"ecosystem_specific":{"binaries":[{"binary_version":"5.1-1","binary_name":"kas"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-54548.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:L/I:L/A:N"},{"type":"Ubuntu","score":"medium"}]}