Concrete CMS before 9.5.3 did not enforce a destination-side authorization check and did not validate a CSRF token in the multilingual page… (CVE-2026-18422)
Concrete CMS versions before 9.5.3 have a vulnerability in the multilingual page assignment backend action where destination-side authorization checks and CSRF token validation were not enforced. This flaw allows an authenticated user with the Edit Page Multilingual Settings permission on a single page to bind arbitrary pages in other locales as translations or delete legitimate translation pairs, impacting language routing on the site. The vulnerability has a low severity rating with a CVSS v4.0 score of 2.1.
AI Analysis
Technical Summary
Concrete CMS before version 9.5.3 did not enforce destination-side authorization checks nor validate CSRF tokens in the Backend\Page\Multilingual::assign action. Consequently, an authenticated user possessing the Edit Page Multilingual Settings permission on one page could manipulate multilingual page assignments by binding arbitrary pages in other locales as translations or deleting valid translation pairs. This impacts the integrity of language routing on the site. The vulnerability is identified as CWE-862 (Missing Authorization). The Concrete CMS security team assigned a CVSS v4.0 score of 2.1, indicating low severity.
Potential Impact
An authenticated user with elevated permission on a single page can alter multilingual page assignments across the site, potentially disrupting public-facing language routing. This could lead to incorrect or maliciously altered translations being presented to site visitors. However, the impact is limited by the requirement for the user to have the Edit Page Multilingual Settings permission on at least one page.
Mitigation Recommendations
A fix is available in Concrete CMS version 9.5.3 and later. Users should upgrade to version 9.5.3 or newer to address this vulnerability. No additional mitigation steps are indicated by the vendor advisory.
Concrete CMS before 9.5.3 did not enforce a destination-side authorization check and did not validate a CSRF token in the multilingual page… (CVE-2026-18422)
Description
Concrete CMS versions before 9.5.3 have a vulnerability in the multilingual page assignment backend action where destination-side authorization checks and CSRF token validation were not enforced. This flaw allows an authenticated user with the Edit Page Multilingual Settings permission on a single page to bind arbitrary pages in other locales as translations or delete legitimate translation pairs, impacting language routing on the site. The vulnerability has a low severity rating with a CVSS v4.0 score of 2.1.
CVSS v4.0
Affected software
pkg:composer/concretecms/concrete5Run on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
Concrete CMS before version 9.5.3 did not enforce destination-side authorization checks nor validate CSRF tokens in the Backend\Page\Multilingual::assign action. Consequently, an authenticated user possessing the Edit Page Multilingual Settings permission on one page could manipulate multilingual page assignments by binding arbitrary pages in other locales as translations or deleting valid translation pairs. This impacts the integrity of language routing on the site. The vulnerability is identified as CWE-862 (Missing Authorization). The Concrete CMS security team assigned a CVSS v4.0 score of 2.1, indicating low severity.
Potential Impact
An authenticated user with elevated permission on a single page can alter multilingual page assignments across the site, potentially disrupting public-facing language routing. This could lead to incorrect or maliciously altered translations being presented to site visitors. However, the impact is limited by the requirement for the user to have the Edit Page Multilingual Settings permission on at least one page.
Mitigation Recommendations
A fix is available in Concrete CMS version 9.5.3 and later. Users should upgrade to version 9.5.3 or newer to address this vulnerability. No additional mitigation steps are indicated by the vendor advisory.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-hch9-r5fg-6p72
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2026-18422"]
- Database Specific Severity
- LOW
- Cvss Version
- 4.0
Threat ID: 6aaa07e855bf5e2cf5ea3454
Added to database: 09/16/2026, 03:07:20 UTC
Last enriched: 09/16/2026, 04:57:17 UTC
Last updated: 09/16/2026, 22:01:33 UTC
Views: 3
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