23 Oct 2026 15:48:27 UTC
Concrete CMS before 9.5.4 allows a deactivated user to retain OAuth-authenticated REST API access
cve-program · CVE-2026-85387 · Published
CVE-2026-85387
Concrete CMS before 9.5.4 allows a deactivated user to retain OAuth-authenticated REST API access
CVSS 4.0 2.0 LOWCheck source for fixed versionsKEV status unknown
cve-program · CVE-2026-85387
PublishedConcrete 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.
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