Your version of LimeSurvey: LimeSurvey Community Edition - Version 5.6.68+240625
Own server or LimeSurvey Cloud: Own server
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Hi everyone,
I have created a form with limesurvey, where the user has to upload an electronically signed file in PDF or P7M format.
To do this I used the ‘File upload’ question type made available by Limesurvey.
For PDF files I had no problem, but for P7M files there was no way, I always get this message :
‘The file type application/octet-stream (extension: bin) is not allowed!’.
Searching on intenet it seems that the MIME type for P7Ms may not be interpreted correctly because this configuration on the web server is missing Together with fellow system administrators we have tried various attempts by adding the MIME type to various files (htaccess, config.php, etc.) but without result.
I would like to know if anyone has already been through this and found a safe solution.
Thank you all

Theoretically: there is a solution

1. Get a valid magic_database (see finfo_open PHP function ) with your application/pkcs7-mime
2. Set [url=https://application/pkcs7-mime.]the P7M to application/pkcs7-mime. in a PHP file[/url]
3. Update your config.php to use both of file

When I add this solution, I replace the Old Debian magic_database for a newer magic_database from Fedora, I don't remind the issue, but it allows to work for newer file type. If you manage the server : try to replace it globally on your PHP version.

Maybe you can try with