CVE-2026-15305
published 2026-07-14CVE-2026-15305: Users were able to upload files with arbitrary MIME types to forms using FileUpload or ImageUpload elements with allowedMimeTypes configured. The restriction…
PriorityP340medium6.3CVSS 4.0
AVNACLATPPRNUINVCNVILVALSCNSINSANEXCRXIRXARXMAVXMACXMATXMPRXMUIXMVCXMVIXMVAXMSCXMSIXMSAXSXAUXRXVXREXUX
EPSS
0.25%
16.8th percentile
Users were able to upload files with arbitrary MIME types to forms using FileUpload or ImageUpload elements with allowedMimeTypes configured. The restriction was not enforced server-side because the MimeTypeValidator was registered during form building before concrete form definition properties were applied, resulting in the validator never being added to the processing pipeline. This issue affects TYPO3 CMS versions 14.2.0-14.3.4.
Affected
2 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| typo3 | cms-form | >= 14.2.0 < 14.3.5 | 14.3.5 |
| typo3 | typo3_cms | >= 14.2.0 < 14.3.5 | 14.3.5 |
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GHSA
TYPO3 CMS - Unrestricted File Upload in Form Framework
ghsa·2026-08-31
CVE-2026-15305 [MEDIUM] CWE-351 TYPO3 CMS - Unrestricted File Upload in Form Framework
TYPO3 CMS - Unrestricted File Upload in Form Framework
### Problem
Users were able to upload files with arbitrary MIME types to forms using _FileUpload_ or _ImageUpload_ elements with _allowedMimeTypes_ configured - uploading PHP files was **not** possible. The restriction was not enforced server-side because the _MimeTypeValidator_ was registered during form building before concrete form definition properties were applied, resulting in the validator never being added to the processing pipeline.
### Solution
Update to TYPO3 version 14.3.5 LTS that fixes the problem described.
### Credits
Thanks to Sébastien Convers for reporting this issue, and to Josua Vogel and Oliver Hader for fixing it.
GHSA
Users were able to upload files with arbitrary MIME types to forms using FileUpload or ImageUpload elements with allowedMimeTypes configured.
ghsa_unreviewed·2026-07-14
CVE-2026-15305 [MEDIUM] CWE-351 Users were able to upload files with arbitrary MIME types to forms using FileUpload or ImageUpload elements with allowedMimeTypes configured.
Users were able to upload files with arbitrary MIME types to forms using FileUpload or ImageUpload elements with allowedMimeTypes configured. The restriction was not enforced server-side because the MimeTypeValidator was registered during form building before concrete form definition properties were applied, resulting in the validator never being added to the processing pipeline. This issue affects TYPO3 CMS versions 14.2.0-14.3.5.
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
2026-07-14
Published