{"id":"DEBIAN-CVE-2026-116672","details":"Authlib is a Python library which builds OAuth and OpenID Connect servers. From 0.15 until 1.9.1, the documented ClientConfigurationEndpoint.authenticate_client and ClientConfigurationEndpoint.check_permission reference implementations look up a target client from request-controlled client_id data and check only whether that target is editable, without verifying that request.credential belongs to the target client. Deployments following both examples can allow a client holding any valid registration access token to read, modify, or delete another client's registration. Changing redirect_uris can enable authorization code or token interception, while deleting registrations can deny service to affected clients. This issue is fixed in version 1.9.1.","modified":"2026-10-31T10:00:54.759051675Z","published":"2026-10-27T17:16:59.140Z","upstream":["CVE-2026-116672"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2026-116672"}],"affected":[{"package":{"name":"python-authlib","ecosystem":"Debian:12","purl":"pkg:deb/debian/python-authlib?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.2.0-1","1.2.0-1+deb12u1","1.2.0-1+deb12u2","1.2.1-1","1.3.0-1","1.3.0-2","1.3.0-3","1.3.1-1","1.3.2-1","1.3.2-2","1.4.0-1","1.4.1-1","1.5.0-1","1.5.1-1","1.5.2-1","1.6.0-1","1.6.1-1","1.6.3-1","1.6.4-1","1.6.5-1","1.6.6-1","1.6.7-1","1.6.8-1","1.6.9-1","1.7.0-1","1.7.2-1","1.7.2-2","1.9.1-1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-116672.json"}},{"package":{"name":"python-authlib","ecosystem":"Debian:13","purl":"pkg:deb/debian/python-authlib?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.6.0-1","1.6.0-1+deb13u1","1.6.1-1","1.6.3-1","1.6.4-1","1.6.5-1","1.6.6-1","1.6.7-1","1.6.8-1","1.6.9-1","1.7.0-1","1.7.2-1","1.7.2-2","1.9.1-1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-116672.json"}},{"package":{"name":"python-authlib","ecosystem":"Debian:14","purl":"pkg:deb/debian/python-authlib?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.9.1-1"}]}],"versions":["1.6.0-1","1.6.1-1","1.6.3-1","1.6.4-1","1.6.5-1","1.6.6-1","1.6.7-1","1.6.8-1","1.6.9-1","1.7.0-1","1.7.2-1","1.7.2-2"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-116672.json"}}],"schema_version":"1.9.2","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"}]}