Hi guys, I was looking for matrix.org’s and Element Client’s privacy policies and I saw something that says Matrix and Element shares data with AWS (Amazon Web Service), Cloudflare, Mythic Beasts, UpCloud. Is it safe to use? The matrix.org has good features as FOSS, decentralized etc. But this seem a lil bad. Any experts about prviacy?
When using encrypted chat, message contents are securely encrypted. Attachments as well, as they’re secured by keys exchanged through those some encrypted messages.
Matrix does leak quite a bit of metadata that a few other apps, like Signal, doesn’t leak.
If you’re sharing family photos, it’ll probably be secure enough. If you’re committing crimes or shit talking your oppressive government, probably best to pick something else.
If you’re not comfortable with all the data shared with some of these companies, you may want to find a matrix homeserver with a more suitable privacy policy, and perhaps a matrix client app that doesn’t collect as much data. Do note that some information, such as encrypted attachments, may end up on other servers if you talk to people with accounts on matrix.org. It’s the same as with email: you can use protonmail pretty securely, but if you send an email to @gmail.com, Google may be able to read (parts of) it.
I understood clearly what you said. Thanks for detailed text. The protocol uses end-to-end encryption, yes. But, I didn’t understand what type of information is being leaked. Do you mean e-mails, phone numbers, profile pics etc. as metadata? If I use another server or self-hosted server, can I avoid the leak. And not only matrix.org, Element uses same types of informations. Element’s permissions was a bit high in Android, Flatpak etc. I’m using Element on my GNU desktop and not on phone. No phone number, no profile pic, no e-mail; only username, server and password. Do I still give information?
Information leaked by the protocol is “what user IDs from what servers are in what groups, replying to what other user IDs how often and at what times”. It’s the kind of metadata the NSA collected from Americans that landed them in hot water. This is exchanged between servers and copied over to any server with an account present in the room. This information is encrypted by HTTPS in transit, so it’s not plain readable, but you have to trust every server in a given room not to leak that information.
Things like profile pictures and display/user name can also be derived relatively easily in common use, though it’ll be very difficult to find if you don’t join any public rooms and pick a random looking username.
On a protocol level, there’s no need for you to provide an email address or a phone number. Some services may require these details to prevent spam/account floods, but you can use Matrix without either. The only reason you’re asked for these is that they allow others who have you in their address book to find you, so you can start chatting to people without exchanging usernames. I’ve opted not to use this info in my account.
I don’t know what permissions you found troublesome on Android, though. Everything it asks seems to make sense for a modern messenger with features like video calling and location sharing. There are other apps available for Android, though.
If you use your own server, you’ll be in charge of what information you provide, and you can even firewall off servers that you’re not interested in communicating with if you want. If you join any public rooms you’ll still need to share some info (or the protocol won’t work), but you can do things like configure your server to only permit fetching attachments from whitelisted servers. This isn’t a standard option, but with some knowledge of reverse proxies it’s not impossible to pull off.
Compared to more private, but non-federating, protocols like Signal, Matrix leaks a decent bit of metadata when using encrypted channels. It may even leak more than XMPP, though I don’t really use that as nobody I know still uses XMPP. On the other hand, Signal is centralised on one single server, and if that server goes down, your ability to use the app goes down with it. With Matrix, you can just register on another server.
I would say Matrix is secure enough for everyday chat if you enable encryption (and preferably verify the keys of the people you communicate with), but not a good choice for human rights activists or criminals.
It’s end to end encrypted, it could be hosted on the NSA’s servers for all you care, it should be safe.
The reason this is there is likely because they use those cloud services to provide the hosted services, so they disclose that they do. I don’t think it applies to the client you download or the ones you self-host from open-source builds on your own homeserver on your own infrastructure.
