CVE-2026-81916Incorrect Authorization in the Concrete CMS Express Entries Dashboard below version 9.5.3 Allows Entry Creation in an Unauthorized Object

Concrete CMS before 9.5.3 evaluated the authorization check for an Express entry submission against the entity of the posted form rather than the entity identified by the dashboard route. As a result, a user permitted to add entries to one Express object could create entries in a different Express object outside their authorization scope, potentially polluting protected datasets, triggering workflows, or injecting content into administrative processes. The dashboard submit route resolved the mutated entity from the attacker-controlled route ID while the permission check validated the independently posted form's entity, and the submission proceeded because the two entities were never compared. The Concrete CMS security team gave this vulnerability a CVSS v4.0 score of 5.1 with vector CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N. Thanks Yonatan Drori from Tenzai for reporting.

CVSS

5.1 MEDIUM (v4.0, CNA)CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N

Weakness (CWE)

CWE-862, CWE-639

Known exploited

Not in CISA's KEV catalog

EPSS (exploitation in the next 30 days)

Not loaded for this CVE

Assigned by

ConcreteCMS

NVD analysis

Analyzed

Record last updated

Sep 14, 2026

First seen by InfoSec Signals

Oct 9, 2026

The CVE record on cve.org · NVD's entry

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