Libcli provides a shared library for including a Cisco-like command-line interface into other software. It's a telnet interface which supports command-line editing, history, authentication and callbacks for a user-definable function tree.
Unable to reproduce on a CentOS 7.5 box. Started clitest, then did 'telnet localhost 8000', was prompted for user/password. Using credentials listed in readme was able to log in.
As a reference version, 1.9.3 does not have this problem.