TOR, AKA “The Onion Router”, is described on their web site as follows:
Using Tor can help you anonymize web browsing and publishing, instant messaging, IRC, SSH, and other applications that use the TCP protocol. Tor also provides a platform on which software developers can build new applications with built-in anonymity, safety, and privacy features.
But several security issues have been raised recently with the TOR, and a number of security professionals believe TOR should not be relied upon to provide secure communications or anonymous web browsing.
In fact, TOR provides this warning on their download page:
Warning: Want Tor to really work?
…then please don’t just install it and go on. You need to change some of your habits, and reconfigure your software! Tor by itself is NOT all you need to maintain your anonymity. There are several major pitfalls to watch out for.
Tor only protects Internet applications that are configured to send their traffic through Tor — it doesn’t magically anonymize all your traffic just because you install it. We recommend you use Firefox with the Torbutton extension.
Browser plugins such as Java, Flash, ActiveX, RealPlayer, Quicktime, Adobe’s PDF plugin, and others can be manipulated into revealing your IP address. You should probably uninstall your plugins (go to “about:plugins” to see what is installed), or investigate QuickJava, FlashBlock, and NoScript if you really need them. Consider removing extensions that look up more information about the websites you type in (like Google toolbar), as they may bypass Tor and/or broadcast sensitive information. Some people prefer using two browsers (one for Tor, one for unsafe browsing).
Beware of cookies: if you ever browse without Tor and Privoxy and a site gives you a cookie, that cookie could identify you even when you start using Tor again. You should clear your cookies frequently. CookieCuller can help protect any cookies you do not want to lose.
Tor anonymizes the origin of your traffic, and it encrypts everything inside the Tor network, but it can’t encrypt your traffic between the Tor network and its final destination. If you are communicating sensitive information, you should use as much care as you would on the normal scary Internet — use SSL or other end-to-end encryption and authentication.
While Tor blocks attackers on your local network from discovering or influencing your destination, it opens new risks: malicious or mis-configured Tor exit nodes can send you the wrong page, or even send you embedded Java applets disguised as domains you trust.
Also, the ‘exit servers’ on the TOR network can easily be compromised, and all traffic through an exit router can be misused, as evidenced in the following article:
http://www.securityfocus.com/news/11486?ref=rss
In other words, even if you use TOR, secure communications requires careful configuration and the use of encryption and a secure pipe, such as SSL or VPN. And, as evident in the above article, you may indeed be less secure using the TOR network than when using other means of secure communications because TOR may give users a false sense of anonymity or security.
For secure email, we recommend using an email service that allows full SSL encryption for the entire session, not just the login page. And if you use email through a hosted web site, we recommend that you contact the host and ask if their email is secure or can be made secure. Many cannot.
We recommend any of the following options:
- HushMail, is one of the best.
- Alternatively, Gmail can be made secure if you log in using SSL, as in “https://gmail.google.com”.
- Or set up an Exchange Server account. We recommend Mailstreet, and use it locally or online.
- Or use a secure email installation on your computer. We recommend Ciphire Mail. (for maximum protection, both sender and reciever must be using Ciphire.) Ciphire can secure email using most any email client, such as Outlook.