---
id: CVE-2026-81904
title: >-
  Concrete CMS below 9.5.3 registered view assets for every sub-block of a
  Stack, Container, or layout area without checking whether the requesting user
  could view that sub-block
summary: >-
  Concrete CMS below 9.5.3 registered view assets for every sub-block of a
  Stack, Container, or layout area without checking whether the requesting user
  could view that sub-block. An unauthenticated visitor could recover
  configuration valu…
severity: medium
cvss: 6.3
cvssVector: 'CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N'
cwe:
  - CWE-862
vendor: Concrete CMS
product: Concrete CMS
affected:
  - concrete_cms >= 5 <= 9.5.2
published: '2026-09-08'
updated: '2026-09-10'
sourceUpdated: '2026-09-10T15:17:47.090'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-81904'
references:
  - url: >-
      https://documentation.concretecms.org/9-x/developers/introduction/version-history/953-release-notes
    label: ff5b8ace-8b95-4078-9743-eac1ca5451de
tags:
  - nvd
  - cve.org
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-09-10T14:45:32.599625Z'
cvssSource: cna
epss: 0.0046
epssPercentile: 0.373
ingestedAt: '2026-09-08T22:12:30.991Z'
---

## Overview

Concrete CMS below 9.5.3 registered view assets for every sub-block of a Stack, Container, or layout area without checking whether the requesting user could view that sub-block. An unauthenticated visitor could recover configuration values emitted by a restricted sub-block's asset registration — such as a site's configured Google Maps API key — from any public page embedding an affected Stack, Container, or layout area, despite the block-level permission restriction. Any sub-block type whose asset or header hooks output configuration values is affected.  The Concrete CMS security team gave this vulnerability a CVSS v.4.0 score of 6.3 with vector CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N. Thanks Yonatan Drori (Tenzai) for reporting.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.