Recently I bought a MTS MBlaze 3G Plus Wi-Fi USB Modem.  I picked it because, it got pretty good tariff plans & speed compared to other providers in my area. The interesting thing is that, it allowed up to 5 devices to connect to it via Wi-Fi. So it appears to me as a fast, cheap and portable broadband alternative.  This device is manufactured by ZTE, a Chinese multinational telecommunications equipment and systems company.
MBlaze has two way of operation :-
- Connect to Computer and use it like any other USB Net setter.
 - Connect to a 5V charger and it will start a Wi-Fi network with connectivity up to 5 devices.
 
- As I am a Security Guy, I checked the Router web interface of the device and was surprised to see hell lot of vulnerabilities in a new Device.
 
- One thing I noticed is that Wi-Fi WPA/WPA2/WEP Key is shown as plain text in the text box.
 
  | 
| MTS MBlaze Wi-Fi Password | 
- After some digging outs, it was found that the passwords are hard coded in the source code. 
 - The router web interface password is hard coded in the password reset page.
 
  | 
| MTS MBlaze Router Credentials | 
- The worst thing was that the session maintaining cookie used by the router web interface is static. This Cookie (iusername=logined) is all you need to get an authenticated session. 
 - As this session cookie is constant all the times, simply setting the cookie will give access to protected pages in the web interface.
 - Another issue  I found was, that you can reset the router web interface password without knowing old password. You don’t even need the session cookie for password resetting. 
 - The following request is a PoC to reset the password without knowing the old password and with an unauthenticated session. 
 - This will be considered under OWASP Top 10- A4, Insecure Direct Object Reference.
 
   POST /goform/formSyWebCfg HTTP/1.1 Host: 192.168.1.1 Content-Type: application/x-www-form-urlencoded Referer: http://192.168.1.1/en/password.asp Accept-Encoding: gzip,deflate,sdch Accept-Language: en-US,en;q=0.8,es;q=0.6,ms;q=0.4 Content-Length: 52 action=Apply&sys_cfg=changed&sys_password=newpass  |  
- Most of the forms in the Router web interface lacks CSRF tokens which essentially make them vulnerable to Cross Site Request Forgery.
 - Putting it all together, I made a quick dirty python POC exploit for MTS MBlaze Ultra Wi-Fi / ZTE AC3633 that can do the following things.
 
- Bypass Login
 - Extract IP Address, Subnet, Gateway Information
 - Steal Router Credentials
 - Steal Wi-Fi WPA/WPA2/WEP Key
 - Reset Password without old password and valid session
 - List out the CSRF affected pages
 
Attack Scenario :-
- Initially attacker will exploit CSRF and make the victim to visit a page containing the following IFRAME
 
   <iframe src="http://192.168.1.1/goform/formSyWebCfg?wl_encryption_protocol=3&wl_ wpa_psk_mode=0&wl_wpa_psk_key=xboz&wl_auth_mode=0&oem_cfg=changed&action=Apply"  width="0" height="0">  |  
- Now the Wi-Fi Key is changed to xboz. From this point, the attacker can connect to the Wi-Fi network and  execute the exploit to gain access to the MTS device. 
 
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