GHSA-mfqj-cqv3-h7xw: Composer/typo3/cms-form vulnerability
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.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
composer/typo3/cms-formto a version that resolves this vulnerability.Fixed in 14.3.5 - Upgrade
Upgrade
TYPO3to a version that resolves this vulnerability.Fixed in 14.3.5
Event History
Frequently Asked Questions
Which deployments are exposed to this issue?
The issue applies to forms that use FileUpload or ImageUpload elements with allowedMimeTypes configured. The advisory does not state whether these elements or MIME-type restrictions are present in default form configurations.
What would an attacker need to do to exploit it?
An attacker would need access to submit a form containing an affected upload element. They could upload a file using an arbitrary MIME type despite the configured allowedMimeTypes restriction.
Are PHP files included in the arbitrary file-upload behavior?
No. The advisory explicitly states that uploading PHP files was not possible.
What is the remediation?
Update composer/typo3/cms-form to TYPO3 version 14.3.5 LTS, which fixes the missing server-side MIME-type validation.