Party like you’re on a 1990’s network

Posted in avoidable vulnerabilities on January 26th, 2015 by Blog Operations

It’s 2015. And yet some vendors are still shipping network-attached devices like… well, at least like it’s 1999, if not before.

We’re talking about Telnet. In 2015, do not use Telnet. It’s unencrypted and it can leak passwords to an adversary. This is not a news flash.

Telnet was really cool back in the day. The user┬ádidn’t have to be in front of the computer they wanted to access. They could – gasp – connect remotely.
In the intervening decades since telnet was first introduced, we’ve learned a few things about network security. For example, it’s bad to use unencrypted protocols if it can be avoided, specifically where an adversary could trace a password. Console connections through the “telnet” protocol are “in the clear” because they are exposed.

Telnet was developed last century. Here in the future in 2015, you can’t assume anything about the network between you and the remote device you’re logging in to. You have to assume somebody’s going to wire tap it. Either the bad guys, or some off-the-reservation sysadmin, or who knows what else. This means you have to assume any password you type into telnet is really in the clear. What should you do? Don’t run telnet. Use SSH or some other protected mechanism. At this point in the 21st century telnet is really quaint, outdated and sort of scandalously unsafe.

This happens repeatedly. Apparently we have to keep reinforcing this concept. See this post from 2011…
I’d like to tell you I’ve not seen telnet deployed in new vendor products but it’s January 2015 and I’ve seen one this year already.

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