---
id: CVE-2026-18120
title: >-
  Concrete CMS before 9.5.3 exposed a legacy Express entry search endpoint that
  returned entry result JSON without invoking the canViewExpressEntries()
  permission check applied by the normal dashboard and CSV Export flow
summary: >-
  Concrete CMS before 9.5.3 exposed a legacy Express entry search endpoint that
  returned entry result JSON without invoking the canViewExpressEntries()
  permission check applied by the normal dashboard and CSV Export flow. An
  unauthenticate…
severity: medium
cvss: 5.9
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N'
cwe:
  - CWE-862
vendor: concretecms
product: concrete_cms
affected:
  - concrete_cms < 9.5.4
patched:
  - concrete_cms 9.5.4
published: '2026-09-16'
updated: '2026-09-21'
sourceUpdated: '2026-09-21T17:51:22.957'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-18120'
references:
  - url: >-
      https://documentation.concretecms.org/developers/introduction/version-history/953-release-notes
    label: ff5b8ace-8b95-4078-9743-eac1ca5451de
tags:
  - nvd
  - cve.org
epss: 0.00272
epssPercentile: 0.17592
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-09-17T17:31:34.982550Z'
scores:
  nvd: 5.9
  cna: 6.3
ingestedAt: '2026-09-16T18:01:17.462Z'
---

## Overview

Concrete CMS before 9.5.3 exposed a legacy Express entry search endpoint that returned entry result JSON without invoking the canViewExpressEntries() permission check applied by the normal dashboard and CSV Export flow. An unauthenticated visitor who knew or discovered an Express entity identifier could enumerate that entity's entry search results, disclosing attribute values intended to be restricted to privileged users. For Express entities that do not support entry-specific permissions (i.e., supportsEntrySpecificPermissions() returns false), per-entry permission filtering is additionally disabled via EntryList::ignorePermissions(). The Concrete CMS security team gave this vulnerability a CVSS v4.0 score of 6.3 with vector CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N. Thanks Daniel Powell for reporting.

## Affected

- `concrete_cms < 9.5.4`

## Remediation

Upgrade past the affected range:

- `concrete_cms 9.5.4`