Visforms 6.1.2: JPG Upload rejected although file extension is allowed

Hello,

I found a possible regression/bug in Visforms 6.1.2 regarding file uploads.

Environment:
- Joomla 6.1.0
- PHP 8.2
- Visforms 6.1.2
- Visforms Subscription 6.1.2

Problem:
A JPG file upload is rejected in the frontend although the allowed file extensions are configured correctly.

Allowed extensions:
jpg,jpeg,pdf

Frontend error:
"This file type is not supported"

Important:
- The same JPG file works perfectly on another website
- Same browser
- Same PC
- Same file
- No issue with Joomla media configuration

Comparison:
Working installation:
- Joomla 5.1.5
- Visforms 5.6.2

Problematic installation:
- Joomla 6.1.0
- Visforms 6.1.2

Additional tests:
- Added jpg,jpeg,png,webp,pdf
- Cleared Joomla and browser cache
- Tested different browsers
- Joomla media settings are correct
- "Restricted upload" disabled

Result:
After downgrading from Visforms 6.1.2 to Visforms 6.0.1 the upload works immediately again without changing anything else.

Therefore this seems to be a regression in Visforms 6.1.2 related to MIME type / upload validation.

Best regards

Hello peppermintde,

Thank you very much for the very clear, comprehensive, and—at the same time—compact presentation of the problem, as well as for the version information.

The error occurs in both of the following cases:
- 1. The allowed file extensions are set in the field configuration.
- 2. The allowed file extensions are set in the form configuration.

The file extensions are entered as a comma-separated list.
In this specific error scenario, the first and the last file extensions in the list are always the ones affected.
The cause lies in two single quotation marks ('') that became superfluous following the major refactoring of the Visforms JavaScript code.

We consider this a bug in Visforms and will adjust the behavior.
I created a development issue in the bug list:
Issue [VF-1734] Forum: JPG Upload rejected although file extension is allowed

When we release the bug fix, you will be explicitly informed about the release here in the topic.
There may also be a file-based hot fix for this bug in the very short term.
Thank you again for your report!

Kind regards, Ingmar

Hello peppermintde,

There is a hotfix to resolve the error for:
Joomla 6 and the current Visforms version 6.1.2

Please back up the old file first in case unexpected problems arise.

Download the following file:
- vi-solutions.de/forum-bugfixes/FileField.php_6.1.2.txt
Rename the downloaded file to
- FileField.php
Using the downloaded and renamed file, overwrite the following file on the server:
- components/com_visforms/src/Lib/Field/FileField.php

Kind regards, Ingmar