This tool is used for creating a telnet combo list by using an list of ip adress. It will try a dozen of default password and send you the result in stdout and in a file.
Install the app on the server
user@domain:~# git clone https://github.com/Inplex-sys/telnet-bruter.git
user@domain:~# cd ./telnet-bruter/
user@domain:~# gcc ./*.c -o telnet-bruter -pthread -std=c99 -fcommon
user@domain:~# zmap -p 23 | ./telnet-bruter <threads>