As evidence, the lawsuit cites unnamed “courageous whistleblowers” who allege that WhatsApp and Meta employees can request to view a user’s messages through a simple process, thus bypassing the app’s end-to-end encryption. “A worker need only send a ‘task’ (i.e., request via Meta’s internal system) to a Meta engineer with an explanation that they need access to WhatsApp messages for their job,” the lawsuit claims. “The Meta engineering team will then grant access – often without any scrutiny at all – and the worker’s workstation will then have a new window or widget available that can pull up any WhatsApp user’s messages based on the user’s User ID number, which is unique to a user but identical across all Meta products.”
“Once the Meta worker has this access, they can read users’ messages by opening the widget; no separate decryption step is required,” the 51-page complaint adds. “The WhatsApp messages appear in widgets commingled with widgets containing messages from unencrypted sources. Messages appear almost as soon as they are communicated – essentially, in real-time. Moreover, access is unlimited in temporal scope, with Meta workers able to access messages from the time users first activated their accounts, including those messages users believe they have deleted.” The lawsuit does not provide any technical details to back up the rather sensational claims.
This shows you don’t understand the exploit being used.
Go hang out with Alice & Bob all you want, they aren’t breaking encryption.
I guess c/technology is the same as r/technology, full Smug fools that don’t read articles or understand real world security, but think they are 1337 hax0rm3n
Sorry but you’ll need to hold the L on this one. If I encrypt a message with public key material for which the only private key material that can decrypt the message is in only my possession, it doesn’t matter if the message passes centralized servers.
I’m not trying to be rude, that’s just how it works.
People not understanding how security threats actually work is why everything is so broken these days.
If you do it by hand sure.
If you put the message into an app then the app is trusted to not leak the message. What is described in the article is that Whatsapp can instruct clients to send a copies of the message from the app to their server.
There is nothing stopping any messaging app doing this, having decentralized servers and 3rd party clients wouldn’t stop this but it would make it much easier to protect yourself from the attack.
Your threat model seems to be an app whose published source code doesn’t match the published app, and whose published version uses a side channel not in the source code to leak messages in plaintext to a server. If that’s what we’re worried about then decentralization of the app’s main messaging channel makes no difference. The sneaky side channel could still be there in any app, centralised or decentralized.
That’s a theoretical worry to be mitigated through integrity checks on published open-source apps. The worry with Meta and WhatsApp is much more immediate: a known bad actor with a closed-source app, many domains they could use to leak keys or unencrypted messages, and a fawning relationship with the fascist and surveillance-hungry US Government. I’d still put significantly more trust in Signal even though it is centralised.
You’re right decentralization would help because you could isolate yourself from the corporate server sending the instructions for you to leak the messages.
But ultimately you’re right integrity checks of apps are a better way to address this and fortunately it seems Signal do produce reproducible builds. https://github.com/signalapp/Signal-Android/blob/main/reproducible-builds/README.md so is secure from this kind of attack (unless there is a backdoor in the published code)
Even in an “insecure” app without air-gapped systems or manual encryption, creating a backdoor to access plaintext messages is still very difficult if the app is well audited, open source, and encrypts messages with the recipient’s public key or a symmetric key before sending ciphertext to a third-party server.
If you trust the client-side implementation and the mathematics behind the symmetric and asymmetric algorithms, messages remains secure even if the centralized server is compromised. The client-side implementation can be verified by inspecting the source code if the app is open source and the device is trusted (for example, there is no ring-zero vulnerability).
The key exchange itself remains somewhat vulnerable if there is no other secure channel to verify that the correct public keys were exchanged. However, once the public keys have been correctly exchanged, the communication is secure.
Well audited is key, this attack likely works by doing something like adding Meta to the list of trusted devices, then hiding itself from the list (either because of code in the client or because it the meta device is only added for a moment), so the backdoor wouldn’t be send_all_messages_to_hq(), it would be in the code to list trusted devices, either explicitly hiding some devices or some sort of refresh timer that’s known so you can avoid being there when the UI is updated).
Or it works through the some other mechanism that still preserves E2E encryption.
I assumed that not only the entire app but also the entire client device had been audited. This was a client-side attack, not Meta momentarily adding itself to the trusted-device list. I’m confident it was a client-side attack because it would be impossible to hide even a momentary change in keys from the client without modifying the client app to conceal such a change.
Does WhatsApp make it visible when you add a new trusted device? Does Signal?
But yeah Meta have full control of the client and it isn’t audited so they could do it a lot of ways.
Yes, it is visible when a new trusted device is added. The QR code you scan to link a device contains a one-time public key for that device (ECC is used partly to fit the public key more easily into a QR code). Signal on the phone then sends a lot of information, including the identity keys, to the new device. The new device uses these identity keys to communicate. Note that the transfer of identity keys is fully encrypted, with encryption and decryption taking place on the clients. This can, of course, be bypassed if someone you’re talking to has their security key compromised, but the same risk exists if the recipient takes a screenshot or photographs their device’s screen.
Edit: The security key refers to the one-time key pair generated to initiate the transfer of identity keys and chat history. It can be compromised if someone accidentally scans a QR code and transfers their identity keys to an untrusted device.
I’m not following. In the WhatsApp case, yes, because we can’t see how those keys are managed. In the Signal case, we can. So the centralized server has zero impact on the privacy of the message. If we trust the keys are possessed only by the generating device, then how does the encrypted message become compromised?
I’m not talking about anonymity, only message privacy. No different than any of the other proxies or routers along the way. If they don’t have the key, the message is not readable.
Now I’m curious: how does the person you’re messaging get the same key to decrypt the message you send?
I’m genuinely curious.
They share it with you. Their public key is generated by them. You encrypt a message to them with their public key. They use their private key to decrypt it.
I want to add before I get completely roasted here, that this is intentionally reductive. Signal actually uses a much more interesting multikey sharing algorithm, double ratchet. This uses onetime keypairs, and really is worth reading about.
Is that vulnerable to an attack if a hacker gets their public key and intercepts the data traffic? Or can it only be used to encrypt but not decrypt?
Or are the added layers of complexity designed specifically to prevent that from happening?
This is why I like open-source, because people who know more about it than I do can check everything over and say whether it’s good.
Actually great questions. Yes and no. There are vulnerabilities if the private key leaks, but public keys are just that; perfectly okay public in any hands. You only encrypt data with it.
What makes the Signal protocol so awesome, and other algorithms like it, is that it reduces the threat surface area further by using onetime keys. So even if your key is leaked, it cannot be used to decrypt old or forthcoming messages as the keys have already ratcheted to the next pair.
That’s so interesting. Data kind of blows my mind. Like, how could all that information travel over wires or through the air and not get mixed up with other information on its way to its destination?
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The centralized server is only important because it sends you the message to get around the encryption (either adding a new client to your list of trusted clients or in some other way getting your client to send your messages to Meta).
Because the client is capable of adding the backdoor, it isn’t comprosing the encryption. When you add a desktop client to your Signal account it doesn’t break E2E encryption either but your messages are visible in more places. That (or something like it) is what is being described, Meta aren’t decrypting your messages as they go through their E2E network, they are tapping them client side.
The “exploit being used” is closed-source, proprietary code sending data where it says it doesn’t.
People have already explained to you how signal’s open-source, auditable, and reproducible code prevents the possibility of a similar exploit.
You’re the smug fool who doesn’t understand cybersecurity. How much is zuck paying you to say “signal’s just as bad as whatapp”?
Nobody is saying signal is just as bad, simply that it’s not invulnerable to this kind of attack, even with reproducible builds, especially as we don’t know how the attack works.
When is the last time you checked the linked-devices tab in signal?
Dude…your comments here clearly display that you do not have a single clue as to how cryptography works. You should just pack it up in this thread and head on down the road.
Dude, your comments clearly display that you do not have a single clue as to how security works. You should just pack it up in this thread and head on down the road.
WhatsApp’s cryptography isn’t broken, the app is.
🤣🤣🤣
You need a juice and a nap, Ke-mo sah-bee.