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Swedish security researcher exposes plaintext passwords found while sniffing Tor

10pm, 12th September 2007 - Geek, Rant, News, Web, Security, Legal

Tor: The Onion RouterAs reported on Ars Technica, The Register, Heise Security and Slashdot, the Swedish security researcher Dan Egerstad of DEranged Security has thrust into the limelight a security issue that has been plaguing concerned security technicians for years. Unfortunately, many of the news stories either miss the point entirely or misrepresent Tor as being something it is not and the security vulnerability as being something it, too, is not.

Tor (The Onion Router) aids anonymity. Anonymity is closely related to privacy. Privacy and security often go hand in hand. Therefore, Tor is a secure network.

Wrong ! Three of the above statements are correct but the conclusion drawn from those is not. Tor is not a magic silver bullet for security and privacy. You can't just hook up to the Tor network and expect that everything you do is now secure.

Now that I have that off my chest, let's look at the security research. Research that, completely coincidentally, a friend of mine and I had been discussing last week in our own attempt to do a very similar thing: Find an appropriate point on a network, set up a packet sniffer and publish every username/password combination we find in an effort to push the encrypted logins only agenda. We're in favour of SSH over Telnet or rlogin, scp over rcp, SFTP over FTP and HTTPS over HTTP.

It's always interesting looking at what people actually choose as passwords. Some of them look to be a good mix of uppercase letters, lowercase letters and numbers, some are just lowercase and numbers, some are just lowercase and some are just numbers. I saw one that was 13 random characters long and another that was literally '1234'. I also saw 'temp' and 'Password' as passwords. I did see a few passwords that had symbols but none with any special characters. (Considering that most of these embassies speak languages other than English, this seems strange...) Even without the aid of packet sniffers, some of these passwords seem trivially easy to brute force.

Some people didn't quite understand what had happened. I'm not mentioning any names but don't fret; Dan did. Dan's site was taken down as requested. There's a well known saying about horses and stable doors that seems to apply here. Worse still, Dan's site had (and still has) instructions on what the actual vulnerability is and why it's a problem. Something that most of the news stories about his research failed to pick up on.

Now, on to the debacle of Chinese whispers around any news site catering to pseudo security that ensued. Each one quoting the last one until the message was completely lost. I suspect that The Register were deliberately sensationalising their headline: "Tor at heart of embassy passwords leak" just to get a few extra readers. Many of the news stories focussed on the fact that it was a Tor exit node that the sniffer was running on when in fact this was merely incidental to the real story. Let me state this very clearly: This could have been ANY machine on the route between the client and the server. Tor made it relatively easy for Dan to get on that route but it's certainly possible to achieve without Tor. The vulnerability is that the usernames and passwords are sent in plain text across an untrusted network (and what network of any moderate size can be trusted ?)

There have been some moderate and intelligent responses to all of this. If you filter your Slashdot discussion just the right way, some serious insight (rather than incite) can be gained into issues associated with the one raised. One user points out that Tor should not be used for tasks that can identify you. Another responds that sometimes you want to hide not who you are but where you are. Yet another user suggests that employees would be fired from government positions for using Tor.

One thing missing, however, is a sense of concern about the implications of this. Everybody seems to be treating it as a warning: Look what could happen if you don't encrypt your network traffic. Bad people could get hold of your passwords ! But what if the people logging in to these email accounts are not the employees we think they are ? Why would an employee need to log in to their own, personal email via Tor ? Why would a terrorist need to log in to an embassy employee's email account using Tor ? The second question appears to be somewhat easier to answer and somewhat harder to digest.

My thought is that Dan Egerstad has missed the real significance of the Tor network, possibly because he was already focussed on Tor in his research and hence didn't see it as an unusual element. The real significance is that these accounts may have been compromised some time ago and the original attackers are regularly reading all of these email accounts, simply using Tor as a method to remain anonymous. They probably have comparable hacking skills as the security researcher who exposed the problem and have enough concern about their own anonymity to take steps to ensure they retain it. The best our officials can come up with is a request to remove Dan's website from the internet. Now there's a worrying thought.

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