The telnet client protocol can be abused by a malicious server to read the environment of the client site. The information can be used as preparation for further attacks. This bug can also be exploited by using the telnet:// URL on a web-site and letting the web-browser fork a telnet client. This bug was reported by iDEFENSE [IDEF0865]. Note that this patch changes the behaviour of the telnet client regarding the rule of exported environment variables. Please consult the man page for further details.
With Rapid7 live dashboards, I have a clear view of all the assets on my network, which ones can be exploited, and what I need to do in order to reduce the risk in my environment in real-time. No other tool gives us that kind of value and insight.
– Scott Cheney, Manager of Information Security, Sierra View Medical Center