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By default, Telegram stores a plaintext copy of every message you've ever sent or received on their servers. WhatsApp does end to end encryption using the Sign

by moxie 11y ago

By default, Telegram stores a plaintext copy of every message you've ever sent or received on their servers. WhatsApp does end to end encryption using the Signal Protocol by default, and doesn't store anything server side.

sidcool 11y ago
Cool. So FB/WhatsApp can't even decrypt messages themselves?
- free2rhyme214 11y ago
  He never said that ;)
  - anateus 11y ago
    Yes, he did, elsewhere on this thread.
- nickik 11y ago
  If they actually do what they say the do, then yes. Thier is no evidence that they are lying, so for now its probebly save to assume that they can not read your messages.
  - alias240 11y ago
    No, it is not safe to assume that. Edward Snowden already proved that we cannot trust large US corporations.
    - nickik 11y ago
      Thats what I said. You have to trust them. As far as we know they can not read it. Its fully possible that its not true but its far more likely that it is true. If the work together with the NSA then its more likly that they deploy bad updates to individuels rather then deploying a backdoor to everybody. That is to easy to detect and it would be a marketing desaster.
      - dave2000 11y ago
        No, you said it is safe to assume they can't read your messages, which is the exact opposite to what Snowden said. What you personally think is true, likely etc is irrelevant. Facebook could be compelled to release private keys/data to the US government and not tell anyone and you'd be none the wiser.
MrMullen 11y ago
Don't forget that Telegram uses custom in house encryption and they say "trust us", it's good. Telegram encryption can't be verified.
- dest 11y ago
  As long as the clients are open-source and the encryption is end to end, can't it really be verified? Whatever the server, if the client encryption is reliable, data can't be read on the server side.
  - pfg 11y ago
    if the client encryption is reliable It's not[1]. [1]: https://eprint.iacr.org/2015/1177.pdf https://eprint.iacr.org/2015/1177.pdf
    - janinge 11y ago
      It is not, or was not? Did this issue get rectified by Telegram?
      - CiPHPerCoder 11y ago
        No, they still use MTProto and not an AEAD construction.
        janinge 11y ago
        I was referring to the padding attack. Did they patch this? And are there any property of MTProto that makes it infeasible to replace AES IGE in a later revision of the protocol?
        CiPHPerCoder 11y ago
        The problem isn't IGE. It's that they're using SHA1 (not HMAC-SHA1) in a "MAC and Encrypt" construction.
tuyguntn 11y ago
Does this mean Whatsapp do peer-to-peer message transfer or messages still pass through whatsapp servers?
- nickik 11y ago
  Their is no mobile message app that does peer-to-peer as far as I know. Whatsapp, Telegram, Signal, Actor, Threema all go over a server.
  - nxzero 11y ago
    Why?
    - nickik 11y ago
      Because its very hard to make reliable peer-to-peer apps. Phones are not always reachable easly on the same ip address. They move around, they are sometimes offline, sometimes they have high latency, the network drops most packages, they have limited space and computational power. To deliver a message they both need to be online at the same time. For group messages you need to be very clever to get it working when only part of the people are online. The key destribution is also extreamly difficulte. So lots of problem for very little gain. What would be smart is to have a federated architecture so people can host their own servers and that would solve PART of the same problems, pure peer-to-peer would solve. Actor is devloping in this direction, and they want to get it working with Signal protocol, Signal itself would probebly do it as well if they had the manpower.
    - lmns 11y ago
      Because of NATs and (restrictive) firewalls.
redler 11y ago
When you say Telegram servers store plaintext "by default", does that imply this is not also true of their "Secret Chat" feature? That mode appears to behave as if it's exchanging keys and doing end-to-end encryption... (I am aware of the Telegram flaws you and others have pointed out).
- pfg 11y ago
  "Secret Chat" uses Telegram's (flawed) E2E protocol, so the server would only see ciphertext. A "normal" chat is stored in plaintext. This is also why normal chats work in multi-device environments, but secret chats don't. Unlike iMessage (and I assume Signal - haven't looked at the actual protocol), they don't do anything fancy like making the sender encrypt messages with multiple public keys (one for each device the recipient owns).
  - nahumba 11y ago
    If you know something that telegram doesn`t know, maybe you should contact them, and ask your bitcoins worth of 200,000$ https://telegram.org/crypto_contest https://telegram.org/crypto_contest. Easier to "talk".
    - lox 11y ago
      https://www.schneier.com/crypto-gram/archives/1998/1215.html#contests https://www.schneier.com/crypto-gram/archives/1998/1215.html... http://thoughtcrime.org/blog/telegram-crypto-challenge/ http://thoughtcrime.org/blog/telegram-crypto-challenge/

by moxie 11y ago

sidcool 11y ago

Cool. So FB/WhatsApp can't even decrypt messages themselves?

free2rhyme214 11y ago
He never said that ;)
- anateus 11y ago
  Yes, he did, elsewhere on this thread.
nickik 11y ago
If they actually do what they say the do, then yes. Thier is no evidence that they are lying, so for now its probebly save to assume that they can not read your messages.
- alias240 11y ago
  No, it is not safe to assume that. Edward Snowden already proved that we cannot trust large US corporations.
  - nickik 11y ago
    Thats what I said. You have to trust them. As far as we know they can not read it. Its fully possible that its not true but its far more likely that it is true. If the work together with the NSA then its more likly that they deploy bad updates to individuels rather then deploying a backdoor to everybody. That is to easy to detect and it would be a marketing desaster.
    - dave2000 11y ago
      No, you said it is safe to assume they can't read your messages, which is the exact opposite to what Snowden said. What you personally think is true, likely etc is irrelevant. Facebook could be compelled to release private keys/data to the US government and not tell anyone and you'd be none the wiser.

MrMullen 11y ago

Don't forget that Telegram uses custom in house encryption and they say "trust us", it's good. Telegram encryption can't be verified.

dest 11y ago
As long as the clients are open-source and the encryption is end to end, can't it really be verified? Whatever the server, if the client encryption is reliable, data can't be read on the server side.
- pfg 11y ago
  if the client encryption is reliable It's not[1]. [1]: https://eprint.iacr.org/2015/1177.pdf https://eprint.iacr.org/2015/1177.pdf
  - janinge 11y ago
    It is not, or was not? Did this issue get rectified by Telegram?
    - CiPHPerCoder 11y ago
      No, they still use MTProto and not an AEAD construction.
      - janinge 11y ago
        I was referring to the padding attack. Did they patch this? And are there any property of MTProto that makes it infeasible to replace AES IGE in a later revision of the protocol?
        CiPHPerCoder 11y ago
        The problem isn't IGE. It's that they're using SHA1 (not HMAC-SHA1) in a "MAC and Encrypt" construction.

tuyguntn 11y ago

Does this mean Whatsapp do peer-to-peer message transfer or messages still pass through whatsapp servers?

nickik 11y ago
Their is no mobile message app that does peer-to-peer as far as I know. Whatsapp, Telegram, Signal, Actor, Threema all go over a server.
- nxzero 11y ago
  Why?
  - nickik 11y ago
    Because its very hard to make reliable peer-to-peer apps. Phones are not always reachable easly on the same ip address. They move around, they are sometimes offline, sometimes they have high latency, the network drops most packages, they have limited space and computational power. To deliver a message they both need to be online at the same time. For group messages you need to be very clever to get it working when only part of the people are online. The key destribution is also extreamly difficulte. So lots of problem for very little gain. What would be smart is to have a federated architecture so people can host their own servers and that would solve PART of the same problems, pure peer-to-peer would solve. Actor is devloping in this direction, and they want to get it working with Signal protocol, Signal itself would probebly do it as well if they had the manpower.
  - lmns 11y ago
    Because of NATs and (restrictive) firewalls.

redler 11y ago

When you say Telegram servers store plaintext "by default", does that imply this is not also true of their "Secret Chat" feature? That mode appears to behave as if it's exchanging keys and doing end-to-end encryption... (I am aware of the Telegram flaws you and others have pointed out).

pfg 11y ago
"Secret Chat" uses Telegram's (flawed) E2E protocol, so the server would only see ciphertext. A "normal" chat is stored in plaintext. This is also why normal chats work in multi-device environments, but secret chats don't. Unlike iMessage (and I assume Signal - haven't looked at the actual protocol), they don't do anything fancy like making the sender encrypt messages with multiple public keys (one for each device the recipient owns).
- nahumba 11y ago
  If you know something that telegram doesn`t know, maybe you should contact them, and ask your bitcoins worth of 200,000$ https://telegram.org/crypto_contest https://telegram.org/crypto_contest. Easier to "talk".
  - lox 11y ago
    https://www.schneier.com/crypto-gram/archives/1998/1215.html#contests https://www.schneier.com/crypto-gram/archives/1998/1215.html... http://thoughtcrime.org/blog/telegram-crypto-challenge/ http://thoughtcrime.org/blog/telegram-crypto-challenge/