Security Strategies in Linux Platforms and Applications, 3rd Edition

Helping Users Who Must Use Telnet

While it’s unlikely, there is still a potential for some users to need Telnet. This means, they use some program to communicate in cleartext with a Telnet server. While it’s common to use the Telnet client on the command line, other programs can also implement the Telnet protocol and communicate with Telnet servers. Because Telnet has long been considered insecure, especially since SSH is so widely available, it’s possible there are legacy applications or devices that require Telnet to be used to communicate with them. The problem with this is usernames and passwords as well as a lot of other sensitive information is being transmitted over the wire and can be captured by anyone who has access to the network. ...