CVE-2026-19418: TYPO3 CMS - Broken Access Control in Backend and Install Tool

high Affects typo3/cms-backend, typo3/cms-core. Feed 2026.10.29.1, updated 2026-10-28; published 2026-09-01.

TYPO3 CMS - Broken Access Control in Backend and Install Tool

Package: typo3/cms-backend Composer
Affected versions: >=13.0.0 and <13.4.34
Fixed in: 13.4.34
Severity: high
Exploitation: not on CISA KEV · EPSS 0% (15.3th percentile)
Published: 2026-09-01
Source: osv.dev

References

TYPO3 CMS - Broken Access Control in Backend and Install Tool

Package: typo3/cms-core Composer
Affected versions: >=14.0.0 and <14.3.6 or >=13.0.0 and <13.4.34
Fixed in: 14.3.6, 13.4.34
Severity: high
Exploitation: not on CISA KEV · EPSS 0% (15.3th percentile)
Published: 2026-09-01
Source: osv.dev

References

CWE-346 CWE-352

NVD record typo3/cms-backend advisories typo3/cms-core advisories

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Related advisories

CVE-2009-3631 high TYPO3 Backend Command Injection via Shell Metacharacters in Uploaded File Name same package: typo3/cms-backend
CVE-2010-3663 high TYPO3 Arbitrary Code Execution vulnerability on the backend same package: typo3/cms-backend
CVE-2009-3630 medium TYPO3 Backend vulnerable to Frame Hijacking same package: typo3/cms-backend
CVE-2009-3629 low TYPO3 Backend vulnerable to Cross-site Scripting same package: typo3/cms-backend
CVE-2010-3659 medium TYPO3 Cross-site Scripting vulnerability in the extension manager and backend forms same package: typo3/cms-backend
CVE-2010-3664 medium TYPO3 is vulnerable to Information Disclosure on the backend same package: typo3/cms-backend