Concrete CMS OAuth callback login path prior to version 9.5.3 did not check whether an account was active or email-validated before establishing a session. A deactivated or unvalidated user with an existing OAuth binding could complete authentication and receive a session that was fully authenticated for the callback response, with the login recorded and login events dispatched. The Concrete CMS security team gave this vulnerability a CVSS v4.0 score of 6.3 with vector CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N. Thanks Yonatan Drori from Tenzai for reporting.
Metrics
Affected Vendors & Products
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Advisories
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Fixes
Solution
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Workaround
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References
History
Thu, 10 Sep 2026 23:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | Concrete CMS OAuth callback login path prior to version 9.5.3 did not check whether an account was active or email-validated before establishing a session. A deactivated or unvalidated user with an existing OAuth binding could complete authentication and receive a session that was fully authenticated for the callback response, with the login recorded and login events dispatched. The Concrete CMS security team gave this vulnerability a CVSS v4.0 score of 6.3 with vector CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N. Thanks Yonatan Drori from Tenzai for reporting. | |
| Title | [UNREVIEWED] OAuth Callback Login Bypasses Deactivated-Account Checks | |
| Weaknesses | CWE-288 | |
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| Metrics |
cvssV4_0
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Projects
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MITRE
Status: PUBLISHED
Assigner: ConcreteCMS
Published:
Updated: 2026-09-10T23:20:47.470Z
Reserved: 2026-08-27T18:21:25.200Z
Link: CVE-2026-81906
Vulnrichment
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NVD
Status : Received
Published: 2026-09-11T00:19:48.977
Modified: 2026-09-11T00:19:48.977
Link: CVE-2026-81906
Redhat
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OpenCVE Enrichment
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Weaknesses