CVE-2026-81906

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.

CVSS

No CVSS.

References

Link	Resource
https://documentation.concretecms.org/developers/introduction/version-history/953-release-notes

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-11 00:19

Updated : 2026-09-11 15:17

NVD link : CVE-2026-81906

Mitre link : CVE-2026-81906

CVE.ORG link : CVE-2026-81906

JSON object : View

Products Affected

No product.

CWE

CWE-288

Authentication Bypass Using an Alternate Path or Channel

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