CVE-2026-85387 (GCVE-0-2026-85387)

Vulnerability from cvelistv5 – Published: 2026-09-16 17:12 – Updated: 2026-09-17 17:32
VLAI
Title
Concrete CMS before 9.5.4 allows a deactivated user to retain OAuth-authenticated REST API access
Summary
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.
Severity
2 (Low)
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
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-17 17:32 UTC
CWE
  • CWE-613 - Insufficient Session Expiration
Assigner
ConcreteCMS CNA under the mitre root
CNA scorecard B 84/100 over 111 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Concrete CMS Concrete CMS Affected: 5.0.0 , ≤ 9.5.3 (git)
guessed Create a notification for this product.
Credits
myq_
Show details on NVD website
To clipboard 

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