How to test the upload form for vulnerabilities?

Question

Software testing

Now I'm testing the portal for security. I met information on the net that scripts can be loaded through the loader for subsequent execution on the server. The form filters uploaded files by extension, you can upload the script.php.jpg file, but can this theoretical vulnerability (if it is a vulnerability at all) be promoted. I did not find detailed information on the net.

Answer 1

The form filters uploaded files by extension, you can upload the script.php.jpg file, but can this theoretical vulnerability (if it is a vulnerability at all) be promoted.

Judging by this, the extension is checked not by the magic number, but by a piece of the name, and this is not comme il faut - if the executable file is renamed, then this will not affect its functionality.
However, if you are concerned about .php, .py and similar files, then you also need to check the contents, since these are simple text files.