Problem Backend users with file write permissions were able to upload form definition files with mixed-case extensions (e.g., .FORM.YAML) to bypass the Form Framework's upload restriction. Maliciously crafted form defin…
| CVE ID | CVE-2026-47346 |
| Vendor | composer |
| Affected Product | typo3/cms-core |
| Vulnerability Type | Vulnerability |
| CVSS Score | 7.5 (HIGH) |
| Actively Exploited | ❌ No known exploitation |
| Patch Status | See Vendor Advisory → |
| Reported By | CYBERDUDEBIVASH SENTINEL APEX Intelligence (via github_advisories) |
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Backend users with file write permissions were able to upload form definition files with mixed-case extensions (e.g., .FORM.YAML) to bypass the Form Framework's upload restriction. Maliciously crafted form definition files can be used to execute arbitrary SQL statements, allowing attackers to escalate privileges by creating administrative backend user accounts.
Update to TYPO3 versions 10.4.57 ELTS, 11.5.51 ELTS, 12.4.46 ELTS, 13.4.31 LTS, 14.3.3 LTS that fix the problem described.
TYPO3 CMS thanks Alexander Künzl for reporting this issue, and to TYPO3 core & security team members Oliver Hader and Benjamin Franzke for fixing it.
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