Concretecms Concrete Cms
CVE-2026-85387
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.
What this means for your business
- It affects Concretecms Concrete Cms. It matters if your company, or a supplier that handles your data, runs it.
- An attacker can use it remotely, over a network, with an ordinary user login, and without anyone at your company clicking anything.
What to do
- 1Check whether your company or your suppliers run Concretecms Concrete Cms, and which version. The affected versions are listed further down this page.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
Fastnexa security experts
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Scoring
- CVSS
- 7.1 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N- CVSS v4
- 2.0
- Weakness
- CWE-613
- Assigned by
- ff5b8ace-8b95-4078-9743-eac1ca5451de
Dates
- Published
- 2026-09-16
- Last modified
- 2026-09-21
- Sources
- NVD
Affected products
- Concretecms Concrete Cms- 9.5.4
As listed in the NVD configuration data. Not a statement about your estate.