Is Telegram really an encrypted messaging app? (opens in new tab)

Is it technically possible for them to see it: yes

Does Telegram let them see it: I don't think so. That seems to be the core issue around Durov being arrested.

They probably should implement E2EE for everything. Then they will have a good excuse not to cooperate, because they simply don't have the data.

To me it's a good tradeoff, of course I wouldn't use Telegram for anything illegal or suspect.

I upload encrypted backups to a cloud service provider (AWS, Google Cloud). I go to another computer, download them, use a key/password to decrypt them.

Sure, I get it, you're typing in something that decrypts the data into their app. That's true of all apps including WhatsApp, etc... The only way this could really be secure is if you used a different app to the encryption that you wrote/audited such that the messaging app never has access to your password/private key. Otherwise, at some point, you're trusting their app to do what they claim.

Client creates a Public Private key pair used for E2EE.

Client uses the 'account password (raw)' as part of the creation of a symmetric encryption key, and uses that to encrypt and store the SECRET key on the service's cloud.

NewClient signs in, downloads the encrypted SECRETKeyBlob and decodes using the reconstructed symmetric key based on the sign in password. Old messages can then be decoded.

-- The part that's insecure. -- If the password ever changes the SAME SECRET then needs to be stored to the cloud again, encrypted by the new key. Some padding with random data might help with this but this still sounds like a huge security loophole.

-- Worse Insecurity -- A customer's device could be shipped a compromised client which uploads the SECRET keys to requesting third parties upon sign-in. Those third parties could be large corporations or governments.

I do not see how anyone expects to use a mobile device for any serious security domain. At best average consumers can have a reasonable hope that it's safe from crooks who care about the average citizen.

I found it interesting that countries like Singapore haven’t introduced requirements for backdoors. They are notorious for passing laws for whatever they want as the current government has a super majority and court that tends to side with the government.

Add on top Telegram is used widely in illegal drug transactions in Singapore.

What’s the reason? They just attack the human factor.

They just get invites to Telegram groups, or they bust someone and force them to handover access to their Telegram account. Set up surveillance for the delivery and boom crypto drug ring is taken down. They’ve done it again and again.

One could imagine this same technique could be used for any Telegram group or conversation.

- locally create a recovery key and use it to wrap any other essential keys

- Split that or wrap that with two or more keys.

- N - 1 goes to the cloud to be used as MFA tokens on recovery.

- For the other, derive keys from normalized responses to recovery questions, use Shamir's secret sharing to pick a number of required correct responses and encrypt the Nth key.

You can recover an account without knowing your original password or having your original device.

As an alternative, Signal or Jami conversations are always e2e encrypted.

Telegram would be fine if it advertised itself as a public square of the internet, like Twitter does. Instead, it lures people into false sense of security for DMs and small group chats, which is what Green's post and thus this thread is ultimately about.

Free API doesn't mean anything until they fix what's broken, i.e. provide meaningful security for cases where there's reasonable expectation of it.

Honestly it would be better if Telegram dropped the facade of having E2EE. It's generally very low on the priority list of most people anyway, as much as it would hurt anyone reading this, but that's the truth. People are not using it for secure messaging, but for a better UX and reliability.

EDIT: Telegram does require a phone number to sign up.

It's only on HN I ever see people set up Telegram as some supposed uber-secure private app for Tor users and then demolish that strawman gleefully.

the perceived secure nature of telegram has been memorialized in mainstream rap, courtesy kendrick lamar in 2017 (https://genius.com/11665524).

There is so much misinformation around telegram that alone made me trust it more (if a known liar tries to discredit something, it increases chances of it being good--it is about comments here on HN).

Simply not cooperating with law enforcement is technically moderately difficult, but politically and legally impossible.

Between a difficult and an impossible option, the rational decision is to pick the difficult one.

Given that users can access their messages without interaction with people at Telegram, automatic aggregation of the cloud data for single end points is in place.

In consequence the data can be accessed from a single jurisdiction anyways.

We can be null in cryptography, but handing over both the secret and the key to this secret to the very same person is quite a trustful step, even when they say 'I promise I will not peek or let others peek, pinky promise!' - with an 'except if we have to or if we change our mind' in the small prints or between the lines.

> Translated: Contrary to what has been publicly stated so far, the operators of the messenger app Telegram have released user data to the Federal Criminal Police Office (BKA) in several cases.

https://torrentfreak.com/telegram-discloses-user-details-of-...

> Telegram has complied with an order from the High Court in Delhi by sharing user details of copyright-infringing users with rightsholders.

Anyways just some examples in which their structure doesn't matter. In the end, user data is still given away. It's also why e2ee should be the sole focus. Everything else is "trust me bro it's safe" levels of security.

This is utter bullshit I debunked back in 2021.

https://security.stackexchange.com/questions/238562/how-does...

Or the CEO and owner, staring down the barrel of a very long time in prison, obtains the keys from his employees and provides them to the authorities.

Would he do this? To me, it matters little how much I trust someone and believe in their mental fortitude. I could instead rely on mathematical proofs to keep secrets, which have proven to be far better at it than corporations.

Also

> To this day, we have disclosed 0 bytes of user data to third parties, including governments.

Didn't they conclude an agreement with Russian gvt in 2021?

That's all you need to know. Matrix and Signal can't be forced in any way.

(1) https://youtu.be/1Ut6RouSs0w?t=1082

it’s their own fault. a better question might be:

why do they keep over and over crying when people call them out for endangering their users? it’s super odd.

* https://www.ndss-symposium.org/wp-content/uploads/ndss2021_1...

Generally you need something like TOR to hide who is talking to who.

He's under arrest precisely because it is bad enough that Telegram is in a position to share data with law enforcement, but it chooses not to.

Even so, most messages sent on Telegram are plaintext, they're encrypted only in transport layer, but Telegram's servers see them in full. Secret chats (the only E2EE chats on Telegram) are hidden away from the users, hence the original link.

Telegram channels are public, unencrypted web shops for all kinds of illegal goods. I guess the French government alleges that Durov is not doing enough to stop these activities on his platform.

It doesn't necessarily have anything to do with encryption.

Personally I find Telegram kind of refreshing in nowadays internet landscape where everything is so sanitized. You can discover all kinds of niches you never knew existed.

Do you honestly think that any backdoor would be used for such mundane crimes? Even more so, it being in any way acknowledged that there might be a backdoor?

On that topic, it's highly likely Telegram is cooperating with Russian LE. Services and people that don't get thrown out quickly in Russia.

> The arrest cites that he was not cooperating with authorities to crack down on various drug illegal activities on telegram. [...] None of the other social networks have their ceos arrested.

Because if you want to operate in any country, you're either cooperating with the authorities or you'll get shut down or arrested. Hiding evidence you have is not tolerated anywhere.

We had a nice scandal of sorts here in Denmark where a bunch of young men shared pictures of young women without consent. If you’re old enough to remember those old “rate this girl” web pages from the 90ies you’ll know what the pictures were used for. Basically it was a huge database on hot girls in Denmark and where they went to school. Today around 1000 young men have that on their permanent record as Facebook worked with law enforcement to catch the criminals. Telegram doesn’t do that. This was even a little more innocent that it may sound, considering the men were at least aged similar to the women they were sharing pictures of. Disgusting and illegal, but Telegram houses far worse and refuses to deal with it.

I know a lot of tech minded people are up in arms over this, but it’s really mainly about not wanting an unmoderated social network. Not because big brother is angry, but because people use it to organise bullying, share revenge porn, sell drugs and far, far, worse. There is also political factions within the EU who rants to kill encryption (though they were severely weakened when the brits left), but the anger against SoMe platforms is much more “European”. In that we (and I say this as the EU culture in general, not as in 100% of us) tend to view the people who enable bad behaviour as being participating in that behaviour. Platforms like Facebook, Twitter, Instagram and YouTube have been sort of protected by being early movers with mass adoption. Being American companies probably helps as well considering EU / US relations. Telegram never had such advantages, and is further disadvantaged by how its almost exclusively used for crime in Western Europe.

Obviously banning the platform won’t help. There will just be another platform. But then, we’ve also been losing a drug war for 50+ years even though we can’t even keep drugs out of our prisons.

Because it was so bad he had access to all that content, and because he had access to it, he should have moderated it, and because he didn't he's now arrested.

>Is it simply that telegram is the only one without backdoors for five eyes?

Telegram doesn't have a backdoor. Its open source client can be used to verify it leaks every group message, and every desktop message you ever send, to the service provider without ever applying secret-chat grade encryption

>It seems to me the secret chat feature actually works too well?

Well, Signal can be used to verify its end-to-end encryption is actually used everywhere, but nobody's calling for arresting Moxie or Meredith. So maybe playing 5D-chess over the news isn't working, unless you're here just to amplify this ridiculously fallacious line of thinking.

This is exactly the problem with Telegram. Telegram defaults to client-server encryption for everything, and you can't enable end-to-end encryption for anything on desktop, or group chats ever. Only 1:1 chats and calls on mobile have end-to-end encryption. Client-server encryption is exactly the "100% secure encrypt in wire". When that data arrives to the server, it's no longer encrypted, and Telegram can do whatever it wants with that data, including leaking it to some state actor (like FSB/SVR).

>Anything you type into the chat box is only encrypted by the app after you type and probably storing it in the clear in some local SQLite db.

If endpoint security is of concern, your options with networked TCBs are quite limited. Are you sure the malware doesn't have a chance to escalate its privileges and read messages in clear from RAM?

>It gives them a whole bunch of options to mess with that plain text data.

I'm looking forward to hearing about how you managed to fix this. Should we implement memory as eFuses (https://en.wikipedia.org/wiki/EFuse) to prevent editing logs? What if the user wants to delete his messages?

>Even if the app source code is published as you don’t know if they backdoored it before they submitted to App Store.

E.g. with Signal android, you can pull off the APK from the device, and compare its hash against the client that was reproducibly built from the source code you have in your possession. Been there done that https://imgur.com/a/wXYVuWG

>I am amazed at the low quality comments here.

Too bad you're not exactly improving them with your nonsense.

Um, surely you understand the difference between piping random-looking bytes uselessly to whoever and having a readable copy of all data readily available to whoever hacks the system or applies for a sysadmin role? Or are you making the assumption that people use a closed-source client and the server can push malicious code?

> Even if the app source code is published as you don’t know if they backdoored it before they submitted to App Store.

Doesn't work if you have third parties also working with the system or forking the code to work with it. It gets noticed. Your concept of "e2ee can be 100% leaked anyway" only works if you don't know what code you're running. You need to trust the community in general to uncover issues you've overlooked (in the code or build process) but that's not the same as not having encryption at all. You can't audit the servers but you can audit the client code.

Even worse than Apple. They at least have some e2ee options.

Sure, it may not be on the same level as Signal when it comes to security but it simply is leagues above others in terms of usability, stability and bells&whistles. It's like comparing a Ford Zephyr with a Volvo EX30.

Pretty much, a lot of people think that seeing E2EE means everything is safe, which I believe gives a false sense of security. You can have your phone compromised (especially when I know your phone number, Signal I’m looking at you) or be subject to other means of attacks, exposing everything. I would rather know that this app is not secure so I don’t share anything important, while keeping secure communication to other means.

No idea how secure the encryption is, but calling someone on Telegram is safer than sending texts.

Yes, and that's where the 'practical' argument pops up. With all the E2EE buzz, is it really helping in the scenarios where it's supposed to work the best?

This thread gives an overview on why Signal and other apps are not really practical: https://x.com/Pinboard/status/1474096410383421452

> The broader problem of ephemeral or spur of the moment protest activity leaving a permanent data trail that can be forensically analyzed and target individuals many years after the fact is unsolved and poses a serious risk to dissent. But E2E is not the solution to it.

> I feel like Moxie and a lot of end-to-end encryption purists fall into the same intellectual tarpit as the cryptocurrency people, which is that it should be possible to design technical systems that require zero trust, and that the benefits of these designs are self-evident

Signal does indeed use an architecture (at least for chats with contacts, or optionally everyone when you enable the "sealed sender" option that makes you a bit more prone to receiving spam) where Signal doesn't know who's sending a given message from a given IP address, and only which account it's destined for.

But any entity in position to globally correlate traffic flows into and out of Signal's servers can just make correlations like "whenever Alice, as identified by her phone's IP, sends traffic to Signal, Bob seems to be getting a push notification from Apple or Google, and then his phone connects to Signal, so I think they're talking".

The Internet Is Broken: https://secushare.org/broken-internet

The Hitchhiker’s Guide to Online Anonymity: https://anonymousplanet.org/guide.html

Pointers to more resources: https://discuss.grapheneos.org/d/15005-books-or-sources-on-p...

It is, because you cannot use Signal without giving them your mobile phone number, and from that point onward they (and anyone they might be sharing data with) know the who/what/when, and more. My gut feeling, notwithstanding any apologist and their weak arguments, is that the design choice is exactly about the who/what/when because it's mandatory despite being entirely unnecessary from a technical perspective.

It's a walled-garden system which is fine for private chats between groups of friends, but Discord is increasingly being used as a place to report bugs and share information. Telegram furthermore requires signing up with a phone number which Discord did not (now, often, you need to for participating when an admin of a community aka gild aka misnomer "server" turned on that requirement)

https://xkcd.com/979/ This comic will not be understood by gamers growing up today... (Except in many cases someone posted a solution or nudged DenverCoder9 in the right direction at least; with Discord, Slack, or Telegram you'd simply never find the thread in a search engine to begin with.)

As for applications in use today that address the metadata problem, have a look at Signal's Sealed Sender feature: https://signal.org/blog/sealed-sender/

As for recommending Telegram for secure messages, I side with the sibling comments ("Don't").

If you care about privacy and security, please don't. Defaults matter, and private chats are effectively unusable for anyone using more than one device or needing group chats. And that's not even considering their strange home-baked cryptography.

For metadata you first want to remove the obvious identifiers, phone numbers, names. You'd want to use something like anonymous@jabbim.pl for your IM account.

Next, you'd want to eliminate the IP-addresses from server, so you'd want to connect exclusively through Tor. So you'd set the IM client proxy settings to SOCKS5 localhost:9150 and run Tor client to force your client to connect that way. This is error-prone and stupid but let's roll with it for a second.

Now jabbim.pl won't be able to know who you are, but unless you registered your XMPP account without Tor Browser, you're SoL, they already know your IP.

A better strategy is to use a Tor Onion Service based XMPP server, say 4sci35xrhp2d45gbm3qpta7ogfedonuw2mucmc36jxemucd7fmgzj3ad.onion (not a real one), and you'd register to it via IM client. Now you can't connect to the domain without Tor, so misconfiguring can't really hurt.

So that covers name and IP. We'll assume the content was already end-to-end encypted so that leaks no data.

Next, we want to hide the social graph, and that requires getting rid of the server. After all, a server requires you to always route your messages through it and the service can see this account talks to this account, then to these ten accounts, and ten minutes later, those ten accounts talk to ten accounts. That sounds like a command structure.

So for that you want to get rid of the server entirely, which means going peer-to-peer. Stuff like Tox isn't Tor-only so you shouldn't use them.

For Tor-only p2p messaging, there's a few options

https://cwtch.im/ by Sarah Jamie Lewis (great, really usable, beautiful)

https://briarproject.org/ (almost as great, lots of interesting features like forums and blogs inside Tor)

https://onionshare.org/ by Micah Lee. Also has chats between user and hoster

https://github.com/maqp/tfc by yours truly, crude UX but the security is unparalleled.

>On a side note, I was just recommending Telegram as alternative to WhatsApp

Don't. Telegram and WhatsApp both leak meatadata, but WhatsApp is always end-to-end encrypted. Telegram is practically never end-to-end encrypted. I'd use WhatsApp over Telegram any day. But given that unlike WhatsApp, Signal is open source so you know the encryption works as advertised, it's the best everyday platform. The metadata free ones I listed above are for people in more precarious situations, but I'm sure a whistleblower is mostly safe when contacting journalists over Signal. Dissidents and activists might find Cwtch the best option however.

The fact that you can create a huge group and channels without sharing your phone and contacts is what made Telegram big.

You couldn't do that on WhatsApp until a few months ago. And it has been on Telegram for years. Why Hong Kong protesters used Telegram and not Whatsapp? read this: https://x.com/Pinboard/status/1474096410383421452

The fact that Telegram is massively used in both Ukraine and Russia shows that its model cannot be ignored.

Again, the company lies about queues (a programming technique) being a privacy feature.

The application can not get rid of the metadata of server knowing which IPs are conversing, unless the clients explicitly connect to the service via Tor. The server must always know from which connection to which connection it routes packets. It's not a network hub, it's a switch, after all.

https://cwtch.im/ and https://briarproject.org/ route everything through Tor always, and they don't have server in the middle, which means there is no centralized authority to collect metadata. It's light years ahead of what Simplex pretends to offer.

>Many systems use encryption in some way or another. However, when we talk about encryption in the context of modern private messaging services, the word typically has a very specific meaning: it refers to the use of default end-to-end encryption to protect users’ message content. When used in an industry-standard way, this feature ensures that every message will be encrypted using encryption keys that are only known to the communicating parties, and not to the service provider. From your perspective as a user, an “encrypted messenger” ensures that each time you start a conversation, your messages will only be readable by the folks you intend to speak with.

So and encrypted messaging app means to people the security that an end-to-end encrypted app provides.

He then explains how Telegram is not end-to-end encrypted.

* No end-to-end encryption by default

* No end-to-end encryption for groups, not even small groups.

To add, there's no end-to-end encryption for desktop chats either. And no end-to-end encrypted cross-platform chats either.

Your post reads like dollar-store damage control team post that didn't even read the article they're trying to discredit.

Telegram has had its own history of really weird issues with its encryption protocol, like the IGE, 2^64 complexity pre-computation attacks, IND-CCA vulnerability and whatever the hell this was https://words.filippo.io/dispatches/telegram-ecdh/

But these are not the big issues here. The issues Green's blog post highlighted were

* Telegram doesn't default to end-to-end encryption.

* It makes enabling end-to-end encryption unnecessarily hard

* It has no end-to-end encryption for groups

Those matter gazillion times more than e.g. a slightly older primitive would.

End-to-end encryption matters because Telegram is not just a social media or Twitter wall. It's used for purposes that deserve privacy, and Telegram isn't providing.

It's no wonder why WhatsApp and other apps don't face much heat from the government, they're already with the government.

https://core.telegram.org/reproducible-builds

Their custom encryption is questionable, but since it open source someone would find out by now if there was obvious backdoors.

Telegram is actually one of the only apps I've seen to defend their super-duper secure storage of keys online. All lies of course.

The overwhelming majority of secure messaging apps have no way to recover user data if you drop your phone in the ocean. This includes Signal, Wire, Threema, Session, Element, iMessage etc.

> - you can make a MITM attack on the server (don't know if they do that, but technically possible)

No it's not technically possible, by its very definition. The fundamental principle behind E2EE is that the server can be malicious or compromised all you want, but this does not impact message confidentiality or integrity.

Privacy is a human right. Everyone needs it. And Telegram advertises itself as an encrypted messenger. For every non-expert, that means end-to-end encryption. Only me and recipient can read the message. Users expect Telegram to be more secure than WhatsApp. Telegram claims its more secure than WhatsApp, and Telegram has attacked WhatsApp over its security. WhatsApp is always end-to-end encrypted, Telegram is not. So don't go putting words into peoples mouths.

>Given that they store everything on their servers, it means years of chat history that probably weights Gb for each user

It could be stored there with client-side encryption, Telegram doesn't need to have access to that data. Also who says chats that are ephemeral in nature need to be forever accessible. I save what I need from Signal or Telegram.

>This is the reason Telegram can offer you to have all your messages, including medias that can be up to 1Gb each, stored on a cloud for free.

It's not free. It comes with the price of your human right to privacy. You should get a job at Facebook with this marketing pitch.

>As I user I prefer Telegram just because it's the only app that works perfectly synchronized among multiple devices

It doesn't sync secret chats at all with multiple devices, not even desktop. Signal does.

>good quality native clients

Your script is seven years old https://signal.org/blog/standalone-signal-desktop/

>You can put a backdoor on endpoints, that is compromise the user phone (something they do)

Nirvana fallacy. Why is Telegram offering secret chats if all endpoints are compromised? If they're not always compromised, then it should offer end-to-end encryption for everything, always. Like Signal, Whatsapp, Wire, Threema, iMessage, Cwtch, Briar, Element, Session...

>you can make a MITM attack on the server

Which is why every messaging app worth its salt offers safety numbers https://support.signal.org/hc/en-us/articles/360007060632-Wh...

Even telegram has them, although their initial implementation of babby's first QR-code was a joke. How do you compare over the phone shades of a color matrix?

https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcSUnBRB...

>you can access the data that is backed up on other platform

Oh, that would be horrible. Good thing Telegram doesn't have its data backed up in cloud, no wait, sorry, it does. ~Everything you ever do with the app is permanently stored in an ecosystem built by the Mark Zuckerberg of Russia, and his PhD in geometry bro Nikolai.

Shill harder.

You open the "Telegram nearby" feature anywhere and it's full of people selling drugs and scams. When I mistyped something in the search bar I ended up in some ISIS propaganda channel (which was straight up calling for violence/terrorism). All of this on unencrypted public groups/channels ofc (I'm pretty sure it's the same with CP, although I'm afraid to check for obvious reasons).

I think there is a line between "protecting free speech" and being complicit in crime. This line has been crossed by Telegram.

What a weird hill to die on, given the whole context of this situation.

Do you see public recruitment of people into terrorist cells as a freedom of speech? Do you see publicly selling drugs as a freedom of speech? It isn't about censorship at all, it's about actual *illegal* activity.

Now it's up to Durov and his lawyers to prove that Telegram actually dealt with that. So far France doesn't seem convinced.

Hacker news may 'moderate' illegal content on this website, but they don't have a choice in the matter, US or State authorities will shut them down if they do not, so it's technically censorship. Your view on whether this is good or bad will depend on many factors, one of which may be how you view the legal structure of your government, which is substantially different in France, the US, or Dubai (where Telegram is located).

As is mentioned in the article, Telegram is not simple a 'secure messaging app'. They are also serving a role similar to Facebook, Twitter, Instagram, or TikTok. They host publicly accessible channels or public group chats with thousands of members, which are all (apparently) unencrypted and accessible to the Telegram company. It may be reasonable (both legally and socially) to expect that a company which has knowledge of public, illegal speech to take steps to remove that content from their platform.

And Durov, by choosing to be a media company and not E2E encrypt all of his user's private communications, has walked right into a situation where he needs to abide by local laws moderating/censoring illegal content, everywhere.

What do you mean by users voluntarily submitting to these policies? This distinction seems key in your argument, but I don't see what alternatives to submitting I have here, making it involuntary, right?

https://www.thetimes.com/world/europe/article/pavel-durov-te... “Chief executive of the encrypted messaging app reportedly detained at an airport near Paris over alleged failure to stop criminal activity on the platform”

https://www.tf1info.fr/high-tech/telegram-qui-est-pavel-duro... (one of the largest French newspaper) “Qui est Pavel Durov, le fondateur de la messagerie cryptée Telegram arrêté samedi en France ?”

https://www.google.com/search?q=Telegram+"encrypted+messagin...