CVE-2026-7887
Received Received - Intake
OAuth 2.0 Authorization Bypass in Concrete CMS

Publication date: 2026-05-21

Last updated on: 2026-05-22

Assigner: ConcreteCMS

Description
For Concrete CMS 9.5.0 and below, OAuth 2.0 Authorization-Code Handler Bypasses Account Status. A user with uIsActive=0 (suspended, banned, terminated employee) can still authenticate via OAuth and receive valid API tokens. The Concrete CMS security team gave this vulnerability a CVSS v.4.0 score of 2.3 with vector CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N. Thanks 0x4c616e for reporting.
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Meta Information
Published
2026-05-21
Last Modified
2026-05-22
Generated
2026-06-11
AI Q&A
2026-05-22
EPSS Evaluated
2026-06-10
NVD
CVE-2026-7887
EUVD
EUVD-2026-31364
Affected Vendors & Products
Showing 1 associated CPE
Vendor Product Version / Range
concretecms concrete_cms to 9.5.1 (exc)
Helpful Resources
Exploitability
CWE
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KEV
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CWE ID Description
CWE-1287 The product receives input that is expected to be of a certain type, but it does not validate or incorrectly validates that the input is actually of the expected type.
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Executive Summary

This vulnerability affects Concrete CMS version 9.5.0 and below. It involves the OAuth 2.0 Authorization-Code Handler, which bypasses account status checks. Specifically, a user whose account is marked as inactive (such as suspended, banned, or a terminated employee) can still authenticate using OAuth and obtain valid API tokens.

Impact Analysis

The impact of this vulnerability is that users who should no longer have access to the system (inactive or banned users) can still authenticate and gain valid API tokens. This could allow unauthorized access to protected resources or services, potentially leading to data exposure or misuse.

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