Anyone who uses Facebook apps and WhatsApp on their iPhone runs the risk of spying on the data despite sandboxing and end-to-end encryption can be – by Facebook itself. Whether this is actually done is unknown. However, Facebook always says that they do not have access to the chat data because everything is encrypted end-to-end.
That is so, is due to a peculiarity of iOS. Apple allows developers to put their apps together in so-called App Groups. They can then share their data with each other, says Gregorio Zanon, who has developed a tool for managing iPhone data with iMazing.
Locally, the data is decrypted with an unlocked iPhone, which gives Facebook the opportunity to use the Extend the application so that the WhatsApp data can be transferred unencrypted. But Zanon repeatedly writes that he does not know if this is actually happening. In the database, according to the developer, the phone numbers, names, time code and messages as well as the links to binary attachments.
Zanon writes that WhatsApp has been added to its App Group after its acquisition by Facebook 2014, and would share the directory group.com.facebook.family.