TorChat allows chatting and exchanging files anonymously. This chat client is powered by Tor hidden services, which means that it becomes extremely difficult for a third-party to know the contents of your messages as well as to identify the sender or the recipient.
The application is very easy to use, even more so when you have had previous experience with any chat client. In this respect, you can start by adding your contacts (buddies) by specifying their TorChat IDs and names. Then, initiating a chat session is as simple as clicking on the buddy’s ID and start typing your messages. Likewise, there will be pop-up message to alert you when any of your contacts is trying to reach you.
The power of TorChat to allow secure communication comes from its being based on Tor’s onion-ring services. On top of that, it uses end-to-end encryption to keep your messages private.
Although secure when the attacker does not know the peer's onion address, TorChar still has some flaws that may affect your security. In this regard, a study found that it requests and updates contact lists without the user’s consent, which makes impersonation possible. Likewise, the way its handshake process is implemented allows a potential attacker to perform a communication-confirmation attack.
All in all, TorChat can be useful in those situations in which secure communication is advisable. Yet, it is not completely safe from attacks, which makes it not the best choice when top security is required. The product is opensource and it seems there is no intention in continuing with its development, as it has not been updated in years. Luckily, it has been forked in other similar projects. The version for macOS is an unofficial port of the original project available in GitHub.
Pros
- Uses Tor onion-rings to provide anonymity
- Uses end-to-end encryption
Cons
- Susceptible to impersonation
- May be subject to communication-confirmation attacks