CVE-2026-7887 (GCVE-0-2026-7887)

Vulnerability from cvelistv5 – Published: 2026-05-21 21:20 – Updated: 2026-05-22 13:11
VLAI
Title
For Concrete CMS 9.5.0 and below, OAuth 2.0 Authorization-Code Handler Bypasses Account Status
Summary
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.
Severity
2.3 (Low)
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
CWE
  • CWE-1287 - Improper validation of specified type of input
Assigner
References
Impacted products
Vendor Product Version
Concrete CMS Concrete CMS Affected: 5.0 , ≤ 9.5.0 (git)
Create a notification for this product.
Credits
0x4c616e
Show details on NVD website
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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.