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In Concrete CMS before 9.5.3, the SEO Bulk Update Meta Tags editor did not check per-page edit permissions before saving. (CVE-2026-81923)

0
Low
Published: 09/15/2026 (09/15/2026, 21:31:21 UTC)
Source: GCVE Database

Description

Concrete CMS versions before 9.5.3 contain a vulnerability in the SEO Bulk Update Meta Tags editor where per-page edit permissions were not verified before saving changes. This allowed users with access to the bulk SEO tool, who could view but not edit certain pages, to modify meta titles, meta descriptions, and URL handles of those pages. The vulnerability was assigned a low severity score by the Concrete CMS security team.

CVSS v4.0

Attack Vector
Network
Attack Complexity
Low
Attack Requirements
Present
Privileges Required
High
User Interaction
None
Vuln. Confidentiality
None
Vuln. Integrity
Low
Vuln. Availability
None
Subsq. Confidentiality
None
Subsq. Integrity
None
Subsq. Availability
None
Scope
X
CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Affected software

Packagistmore threats →ai
concrete5/concrete5
pkg:composer/concrete5/concrete5
Affected versions
<9.5.3

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AI-Powered Analysis

Machine-generated threat intelligence

AILast updated: 09/16/2026, 04:58:49 UTC

Technical Analysis

In Concrete CMS before version 9.5.3, the SEO Bulk Update Meta Tags editor failed to check per-page edit permissions during the saveRecord() action. Although the action validated the per-page CSRF token, it did not call canEditPageProperties() for the target page. Consequently, users with access to the bulk SEO tool who could view but not edit certain pages could alter meta title, meta description, and URL handle information, affecting the presentation and live URLs of protected content. The issue is tracked as CVE-2026-81923 and has a CVSS v4.0 base score of 2.1.

Potential Impact

Users with bulk SEO tool access but without edit permissions on specific pages could modify meta tags and URL handles of those pages, potentially altering how content is presented and accessed. This could lead to unauthorized changes in SEO-related metadata and URLs, but does not allow broader content edits or system compromise.

Mitigation Recommendations

A fix is available in Concrete CMS version 9.5.3 that addresses this permission check issue. Users should upgrade to version 9.5.3 or later to remediate this vulnerability.

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Technical Details

Gcve Source
db.gcve.eu
Osv Id
GHSA-4q84-hvmx-qpr3
Osv Schema Version
1.4.0
Aliases
["CVE-2026-81923"]
Database Specific Severity
LOW
Cvss Version
4.0

Threat ID: 6aaa07ea55bf5e2cf5ea3d38

Added to database: 09/16/2026, 03:07:22 UTC

Last enriched: 09/16/2026, 04:58:49 UTC

Last updated: 09/16/2026, 22:01:39 UTC

Views: 3

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