[input_sh]

By default it's no more encrypted than HN (as in, traffic to their servers uses TLS, messages on the server are not encrypted at all).

There's Secret Chats feature which they claim to be end-to-end encrypted, meaning that it's no more secure than Facebook's Messenger (also end-to-end encrypted in Secret Conversations). Even less so considering that they roll their own encryption (MTProto), while Facebook's Messenger uses Signal's protocol.

Further info (which will also lead you to problems with their MTProto protocol, if you're interested): https://security.stackexchange.com/questions/49782/is-telegr...

[ConsiderCrying]

Can we stop using 6-year-old info for apps that get updated monthly? The problems they have with MTProto have been patched literally 5 years ago, the only other criticism comes from a direct competitor, and they recommend WhatsApp despite the fact that it's closed-source and nobody can verify if its encryption truly works.

Facebook is planning to merge Messenger, WhatsApp and Instagram, which makes it even more awful of a choice.

[heinrich5991]

Telegram still doesn't encrypt chats end to end (by default¹), which means it's not a strictly superior choice to WhatsApp.

Facebook can't read your WhatsApp messages (of course they can add an update any time to do that), but Telegram has access to all your messages right now.

¹ Yes, you can select the end-to-end encrypted sessions, but they're very crippled from a usability perspective. I don't remember the last time anyone used it with me, yet all my chats on WhatsApp are end-to-end encrypted without anyone doing anything.

[ConsiderCrying]

> Facebook can't read your WhatsApp messages

Are we sure it can't? Because WhatsApp is closed-source, its GDrive backups are unencrypted and Facebook's whole profit model is based around snooping. Unless they make the app open-source, I'm not trusting them even with a grocery list. People act like E2E is the be-all and end-all but trusting an incredibly shady company on its word is not something I'm comfortable with.

[heinrich5991]

Yes, people are reverse engineering the app. You can check the discussions on HackerNews when security of WhatsApp is discussed.

GDrive backups are not readable by Facebook, they're readable by Google. End-to-end, if properly implemented is the be-all and end-all. Except for metadata, which is a problem, but a different one, and Facebook definitely abuses that. But they don't/can't read the contents of chat messages (for now).

It's not merely trusting that shady company, but also realizing that the news of FB not having E2E-encrypted messages would definitely make the news, you'd be aware of it.

[shawnz]

> It's not merely trusting that shady company, but also realizing that the news of FB not having E2E-encrypted messages would definitely make the news, you'd be aware of it.

Right.. consider what your adversary would be giving up by revealing such a secret, even if it was true. That alone provides a not-insubstantial amount of security.

[baybal2]

> > Facebook can't read your WhatsApp messages

> Are we sure it can't?

Google can remotely uninstall, and install a trojaned version of any app regardless of app signature on an official Android distribution.

[maqp]

"Are we sure it can't?"

No, there's a 1..2% chance of backdoor.

The real question is, why is Telegram more secure? There's a 100% chance it can read your group messages, because it says so on their documentation that describes the cloud encryption. There is no E2EE at all for groups. There is no E2EE at all for desktop. Together these mean E2EE are completely neutered and useless. I'm a privacy researcher and I don't use them at all. Why would an average joe?

[shawnz]

Open source is not the be-all end-all of security either. Closed source apps can still be audited (with increased difficulty), and open source apps might still be impractical to audit even though they are open source.

[maqp]

Nobody's claimed that. Open source is not panacea for verifiable security, it is however a requirement of it.

[shawnz]

No, it is not necessary _or_ sufficient. That is what I'm saying. You can audit a closed-source app, and there also might be open-source apps which are impractical to audit despite them being open source.

[newscracker]

> Facebook can't read your WhatsApp messages

Facebook does get your WhatsApp communication metadata, and has been for years now. As the three letter agencies showed, metadata is actually quite valuable in many respects without needing to trawl through massive amounts of content.

[Mediterraneo10]

Can’t Facebook read most people’s WhatsApp messages because cloud backups of chats are enabled by default, and only the tiny minority of users who disable that feature will get truly end-to-end encryption?

[heinrich5991]

No, that's not true as far as I'm aware. The backup is to Google, not Facebook.

[saagarjha]

I don't see the problem of using a hand-rolled encryption algorithm or the strange choices that went into that algorithm as "patched literally 5 years ago".

[maqp]

"Can we stop using 6-year-old info for apps that get updated monthly?"

The fact Telegram's E2EE has not been available

1. by default

2. on desktop apps

3. for group messages

for seven years tells you exactly how secure it is.

"the only other criticism comes from a direct competitor"

Fuck this attitude. Everyone has the right to criticize. If Telegram can't own their mistakes it's their fault, not that of the people who are beating them. Also, impartial professional cryptographers like Bruce Schneier and Matthew Green have told people not to use Telegram. Why is that if not because it's so horribly insecure. Why isn't there a single recommendation for Telegram from ANY cryptographer on the entire planet?

"they recommend WhatsApp despite the fact that it's closed-source and nobody can verify if its encryption truly works."

Because they've helped implement the encryption? Also if proprietary tools doing encryption are not secure, then why do Telegram users think it's ok for Telegram to use closed-source server that's doing the "distributed datacenter encryption" for group messages' at-rest protection. There's not even documentation available for this let alone source code.

[AsyncAwait]

> The problems they have with MTProto have been patched literally 5 years ag

Really? I haven't seen a single credible audit, nor a clear reason for rolling their own

[input_sh]

Fair point, but from my perspective, even if it was absolutely the best end-to-end encryption there is, it wouldn't mean much unless everyone's using Telegram for 1-to-1 communication using Secret Chats feature.

> Some of its channels helped unconnected, scattered rallies mature into well-coordinated action.

This line alone makes their encryption rather meaningless for this use case, since Secret Chats only work between two people.

[skyyler]

Which is why I'm confused people are even talking about their encryption in this thread.

This has nothing to do with secure chats and everything to do with Telegram's Channels feature. But a ton of people that have never used Telegram nor read the article don't know that.

[sam_lowry_]

And proxies. Telegram has great proxy support and virtually anyone can install their own MTProxy in 5 min.

A multitude of proxies, shadow optic cables over the border and a bit of whitelisting from the government to allow payment processing made Telegram invincible.

[maqp]

Where is their MTProxy tutorial?

[sam_lowry_]

https://github.com/TelegramMessenger/MTProxy

[DavideNL]

> There's Secret Chats feature

But secret chats are only for 1-to-1 chats, not for groups as far as I know (or has that changed?)

[ConsiderCrying]

Nope, hasn't changed and it's one of the things on my "feature wishlist". Really hope they add for at least small chats.

[BTCOG]

Correct. What anyone in an oppressive regime could do though is to make sure settings are set to "share your phone number with no one," as well as delete their own messages from the channel in their entirety after having been read 15-30 min later or whatever arbitrary time they'd like. They would do best to not use an @username or account name which could identify them. Beyond that, there's no way anyone in Belarus can do a thing besides physical violence and take an individual's or a group of people's phones.

There are also options for invite only channels ( I manage several TG channels, public and private) in which nobody can join without having been given the invite link, or added to the channel if their settings permit other users adding them to channels.

[BTCOG]

This is all information in bad faith. The protocol and all Telegram is open source. Are you a cryptographer? And who "rolled" the Signal protocol, Moxie Marlinspike? Did he not design that himself?

[input_sh]

> ...and all Telegram is open source.

This is demonstrably false. Telegram's apps are open sourced (except Telegram X for some reason), same as Signal's (no exceptions). None of the two offer you their server's code.

> And who "rolled" the Signal protocol, Moxie Marlinspike? Did he not design that himself?

It passed the scrutiny of the best cryptographers out there. This comment provides more info: https://news.ycombinator.com/item?id=24237791

And again, this is completely irrelevant because even if Telegram's end-to-end encryption was absolutely the best there is, a) it doesn't work on group chats, and b) it's not enabled by default, only in Secret Chats. The vast majority of Telegram's usage is not end-to-end encrypted at all.

[maqp]

"None of the two offer you their server's code."

Signal server source code:

https://github.com/signalapp/Signal-Server

"The vast majority of Telegram's usage is not end-to-end encrypted at all."

This. This is the backdoor right here. It was never going to be shady flaw in the implementation. It's SO much easier to put it out there in the open, spread misinformation about Telegram being at the forefront of privacy battle and silence all criticism (my links were shadowbanned on their subreddit), and to attack straw men like people posting example's of Telegram's bad track record. tl;dr: damage control.

[maqp]

The protocol and all Telegram is open source.

The open source Telegram client tells us

1. That E2EE is not enabled by default

2. That E2EE is not available at all for group chats

3. That E2EE is not available at all for desktop clients.

So just. No.

"Are you a cryptographer?"

Here's the world's most famous cryptographer, Bruce Schneier saying don't use Telegram: https://www.schneier.com/blog/archives/2016/06/comparing_mes...

Here's the world's second most famous cryptographer, Matthew Green saying don't use Telegram https://twitter.com/matthew_d_green/status/72642891296898252...

Now show me the cryptographer who recommends Telegram. You can't. Because there isn't _any_.

"And who "rolled" the Signal protocol, Moxie Marlinspike? Did he not design that himself?"

No, it was co-authored with Trevor Perrin[1] who is a cryptographer.

[1] https://twitter.com/trevp__

Telegram's encryption OTOH was designed by Nikolai Durov who is not a cryptographer, but a geometrician. That's like asking a gynecologist to perform brain surgery, lol.

[diimdeep]

And how is Signal's protocol is not "roll their own" ? Sorry I don't know.

[tptacek]

Signal Protocol won the Levchin Prize at Real World Crypto, which was awarded by a panel of several of the most renowned academic cryptographers in the field (including Dan Boneh and Kenny Paterson). Other winners include Bellare, Krawczyk, and Joan Daemon. The protocol has been extensively analyzed and is the current gold standard for messaging encryption.

Telegram's protocol... is not that.

[maqp]

This. It's not the Durov brothers who are moving the field of secure messaging onwards, or talking at conferences. They're complete amateurs surrounded by fanboys who don't understand the very basics of the field, and who think copy-pasting from https://tsf.telegram.org/manuals/e2ee-simple makes them useful as opposed to spreading propaganda.

[read_if_gay_]

But the standard we should apply to secure chat protocols isn't how many awards it won, but whether it's watertight. Obviously winning a prestigious prize means it's watertight, but the converse doesn't follow. A protocol can be safe for practical use without winning any prizes.

[maqp]

It can, but given Telegram's history and professional cryptographers like Schneier[1] and Green[2] saying DO NOT USE IT, it's obvious it's _anything_ but watertight.

[1] https://www.schneier.com/blog/archives/2016/06/comparing_mes...

[2] https://twitter.com/matthew_d_green/status/72642891296898252...

[read_if_gay_]

Both four years old. Did they not improve since?

[maqp]

No. Still not E2EE by default, still no E2EE for groups, still no E2EE for desktop clients. Why do you want to imagine Telegram magically got better when it's so obvious it didn't?

[swinglock]

Of course not. You have to first admit you have a problem to be able to improve.

[tptacek]

Does this comment have anything to do with the question I was responding to?

[read_if_gay_]

No, and obviously it doesn't have to, because I'm replying to you. You hint at Telegram's protocol being inferior based on the number of awards it won, a heuristic that isn't too relevant in practice.

[stinkytaco]

First of all, most of this goes back five years and things have likely changed, but basically MTProto used several non-standard and out of date security mechanisms (no AE and using SHA1 were fairly notable at the time) whereas Signal was purposing fairly standard and widely used mechanisms (OTR). It's possible that many of those failures have been addressed over the years, but I haven't followed it closely. It's worth noting that Signal has been widely vetted over time and is the underpinning of WhatsApp, whereas MTProto continues to have a poor reputation, it seems.

[maqp]

The very fact out-of-date security mechanisms passed into first version should tell the developers don't follow their field, or that they're complete amateurs. Both are flags so red Stalin would have a problem with it.

[Mediterraneo10]

The Signal Protocol[0] is based on OTR, a technology which had already seen a number of implementations and informed scrutiny by the time Signal came along.

[0] https://en.wikipedia.org/wiki/Signal_Protocol

[godelski]

Also an important aspect is that it is open sourced, meaning others can audit it. I'm a little untrusting of people that say "trust me" but also "no, you can't look at it." (unless there is a good reason to hide it, which in this case I do not believe there is)

[maqp]

The thing is, there's nothing to audit.

The world's best audit of Telegram would make the following obvious findings:

1. It's not E2EE by default therefore it's not private and secure by default.

2. It's not E2EE at all for groups therefore it's not safe for use of dissident groups

3. It's not E2EE at all for desktop clients therefore it's not practical in daily messaging.

Any audit of the E2EE part is meaningless when E2EE is so impractical it's not used by users at all.

[jhasse]

MTproto is also open source.

[godelski]

Thank you for updating. For those curious this is what I found looking for the source https://github.com/tdlib/td/tree/80c35676a2eb1e9b71db355ee21...

[upofadown]

It's based on the concepts of OTR but it has gone in different directions to actually implement those ideas.

[maqp]

(DH-ratchet is still there. 1536-bit FF-DH was replaced with X3DH etc, but the basic idea is still there. Adding hash ratchet for non-round-trip messaging was a good idea, as was pre-keys stored on server. IMO it's fair to say it's been expanded around OTR)