Django 4.1.9 release notes

May 3, 2023

Django 4.1.9 fixes a security issue with severity “low” in 4.1.8.

CVE-2023-31047: Potential bypass of validation when uploading multiple files using one form field

Uploading multiple files using one form field has never been supported by forms.FileField or forms.ImageField as only the last uploaded file was validated. Unfortunately, Uploading multiple files topic suggested otherwise.

In order to avoid the vulnerability, ClearableFileInput and FileInput form widgets now raise ValueError when the multiple HTML attribute is set on them. To prevent the exception and keep the old behavior, set allow_multiple_selected to True.

For more details on using the new attribute and handling of multiple files through a single field, see Uploading multiple files.