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.
Just because it’s centralized doesn’t mean that it falls under this risk sector. Theoretically if the app was open sourced and was confirmed to not share your private key remotely on generation (or cross sign the key to allow a master key…), then the most the centralized server could know is your public key, the server wouldn’t have the ability to obtain the private key (which is what is needed to read the e2e encrypted messages)
This process would be repeated for the other party. The cool part of that system is you can still share your public keys via the centralized server, so you wouldn’t need to share the key externally. You just need to be able to confirm that the app itself doesn’t contain code to send your private key to the centralized server. Then checking integrity is as easy as messaging your friend to post what their public key is, and that public key would need to match the public key that the server is supplying as your contact.
The server can’t MiTM attack it because the server has no way of deciphering the message in the first place, so the most it could do is pass the message onto the proper party whom has the private key to be able to decrypt it.
Not that I have any other suggestions aside from signal though, there aren’t many centralized e2e chat services. Most use client to server encryption which would allow decryption server side.
The attack as described almost certainly involves the server sending a message to your client and then having the messages replicated via a side channel to Whatsapp without breaking E2E encryption (it could be adding them as a desktop client or adding them as a hidden participant in all chats, that isn’t clear in the article)
If you could run Whatsapp without connecting to Meta, you would be safe from this attack, but as you’ve pointed out a secure client is a better solution.
Fully agree that in this case if the claim is true (they have had a few of these claims), it’s likely whatsapp either making itself a companion app that’s hidden, or has some form of escrow in place to allow deciphering the messages. (Considering Messenger allows decrypting e2e chats with a 6 digit security pin, I’m leaning towards an escrow)
I was just mentioning that this isn’t a fault of it being centralized, this is a design choice by the company when implementing e2e encryption, and that a properly functioning system would never give the server the ability to decipher the messages in the first place.