MTS MBlaze Ultra Wi-Fi / ZTE AC3633 Multiple Vulnerabilities

TL;DR

Multiple Security issues were identified on MTS MBlaze USB Dongle. The post covers how I combined couple of web security issues like Authentication Bypass, Un-authenticated Password Reset, CSRF, IDOR, etc. to develop an exploit for MTS Dongle.

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

1. Connect to Computer and use it like any other USB Net setter.
2. 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.

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.

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.

1. Bypass Login
2. Extract IP Address, Subnet, Gateway Information
3. Steal Router Credentials
4. Steal Wi-Fi WPA/WPA2/WEP Key
5. Reset Password without old password and valid session
6. List out the CSRF affected pages

Download Exploit

GitHub

Screenshot : PoC Exploit

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.

Disclaimer

For Educational and Research Purpose Only.

• Tags: 
• MTS Dongle Exploit
• MTS exploit
• MTS MBlaze exploit
• MTS MBLaze Multiple Vulnerabilities
• MTS MBLaze Password Reset
• MTS MBlaze Ultra 3G Plus
• MTS USB modem exploit
• MTS Wi-Fi Dongle Exploit

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