medium6.3
CVE-2026-15305
Users were able to upload files with arbitrary MIME types to forms using FileUpload or ImageUpload elements with allowedMimeTypes configured.
Impact
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 packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| composer | typo3/cms-form | >= 14.2.0, <= 14.3.4 | 14.3.5 |
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- https://github.com/advisories/GHSA-mfqj-cqv3-h7xw
- https://github.com/TYPO3/typo3/security/advisories/GHSA-mfqj-cqv3-h7xw
- https://nvd.nist.gov/vuln/detail/CVE-2026-15305
- https://github.com/TYPO3/typo3/commit/817ad41cc9dd28aac0fc4d0fe16fc25d46dd554a
- https://github.com/TYPO3/typo3/commit/cfda21050398eb145211a4fa6f9988f10e43e10b
- https://github.com/FriendsOfPHP/security-advisories/blob/master/typo3/cms-form/CVE-2026-15305.yaml
- https://news.typo3.com/security/advisory/typo3-core-sa-2026-020
- https://typo3.org/security/advisory/typo3-core-sa-2026-020