{"id":"CVE-2026-85387","summary":"Concrete CMS before 9.5.4 allows a deactivated user to retain OAuth-authenticated REST API access","details":"Concrete CMS before 9.5.4 re-authorized OAuth REST API requests from the bearer token alone and did not re-check the state of the account the token had been issued to. The resource server's authorization validator confirmed only that a token existed, had not expired, and had not been explicitly revoked, and deactivating a user did not revoke that user's outstanding tokens. As a result, a deactivated user retained full access to /ccm/api/1.0/* for the remaining lifetime of any token already issued to them. The same gap applied to accounts that had been deleted or locked pending a forced password reset. The Concrete CMS security team gave this vulnerability a CVSS v4.0 score of 2.0 with vector CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:A/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N. Thanks Myq Larson for reporting.","modified":"2026-09-19T03:30:15.632001852Z","published":"2026-09-16T17:12:05.336Z","database_specific":{"cwe_ids":["CWE-613"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/85xxx/CVE-2026-85387.json","cna_assigner":"ConcreteCMS"},"references":[{"type":"ADVISORY","url":"https://documentation.concretecms.org/developers/introduction/version-history/954-release-notes"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/85xxx/CVE-2026-85387.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-85387"},{"type":"PACKAGE","url":"https://github.com/concretecms/concretecms"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/concretecms/concretecms","events":[{"introduced":"0"},{"last_affected":"9379c29cb26a1054208b37507b6869811aa75a32"}],"database_specific":{"extracted_events":[{"introduced":"5.0.0"},{"last_affected":"9.5.3"}],"source":"AFFECTED_FIELD"}}],"versions":["9.5.3","9.5.2","9.5.1","9.5.0","9.5.0RC2","9.5.0RC1","9.4.4","9.4.3","9.4.2","9.4.1","9.4.0","9.4.0RC2","9.4.0RC1","9.3.7","9.3.6","9.3.5","9.3.0","9.3.4","9.3.3","9.3.2","9.3.1","8.4.1","8.3.1","8.2.1","8.2.0","8.2.0RC2","8.1.0","5.7.5.7","5.7.5.6","5.7.5.5","5.7.5.2","5.7.4.1","5.7.3.1","5.7.3","5.7.2.1","5.7.2","5.7.0.4","5.7.1","5.7.0.3","5.7.0.1","5.7.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-85387.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:A/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N"}]}