{"id":"UBUNTU-CVE-2026-123806","details":"python-tuf is a Python reference implementation of The Update Framework (TUF). Prior to 7.0.0, DelegatedRole._is_target_in_pathpattern in tuf/api/_payload.py uses fnmatch.fnmatch, which applies os.path.normcase before matching and makes delegation path authorization case-insensitive on Windows. When a TUF repository has path-based delegations that differ only by case and an attacker-controlled role is visited before the legitimate role, ngclient can accept an attacker-provided target from the wrong delegation for a requested path. Linux and macOS clients are not affected because their path normalization does not change case. This issue is fixed in 7.0.0.","modified":"2026-11-11T09:39:20.940385101Z","published":"2026-05-28T22:46:13Z","upstream":["CVE-2026-123806"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-123806"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-123806"},{"type":"REPORT","url":"github.com/theupdateframework/python-tuf"},{"type":"REPORT","url":"github.com/theupdateframework/python-tuf/releases/tag/v7.0.0"},{"type":"REPORT","url":"github.com/theupdateframework/python-tuf/security/advisories/ghsa-qp9x-wp8f-qgjj"}],"affected":[{"package":{"name":"python-tuf","ecosystem":"Ubuntu:26.10","purl":"pkg:deb/ubuntu/python-tuf?arch=source&distro=stonking"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["6.0.0-2","7.0.0-1"],"ecosystem_specific":{"binaries":[{"binary_name":"python3-tuf","binary_version":"7.0.0-1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-123806.json"}},{"package":{"name":"python-tuf","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/python-tuf?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["5.1.0-2","6.0.0-2"],"ecosystem_specific":{"binaries":[{"binary_name":"python3-tuf","binary_version":"6.0.0-2"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-123806.json"}}],"schema_version":"1.9.2","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N"},{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N"},{"type":"Ubuntu","score":"medium"}]}