WhatsApp launches End-to-End encryption for chat backups; Read details about how it works

WhatsApp uses a technology called End-to-End Encryption, which encrypts a message in a way that only the receiver's device can understand. A message is first encoded before being sent over the air to the receiver, and then the receiver's device decodes it before it is presented in the form of text. The technology protects messages from being read or manipulated by bad actors or third-party applications. 

Previously, the technology was only available to text messages on WhatsApp. In a recent announcement made on September 10, 2021, WhatsApp has announced that it is bringing the privacy feature to chat backups for both Android and iOS devices. Following the rollout, users will be able to save their chat backup on Google Drive and iCloud in an encrypted state. Once encrypted, the chat backups would not be accessible for any online storage host. 

How does end-to-end encryption for backup work?

Currently, WhatsApp allows users to save their chat backup, including media and other files, on cloud storage services like Google Drive for Android devices and iCloud for iOS devices. However, the backup and the files contained within the backup are not encrypted and can be manipulated by hackers, bad actors or security agencies as well. With End-to-End encrypted backups, messages and media stores on cloud storage will be encrypted with a completely unique and random key. Users will also be given an option to set a password to access the backup. 

In a white paper released by WhatsApp to explain the technology behind end-to-end encrypted backups, WhatsApp says, "With the introduction of end-to-end encrypted backups, WhatsApp has created an HSM (Hardware Security Module) based Backup Key Vault to securely store per-user encryption keys for user backups in tamper-resistant storage, thus ensuring stronger security of users’ message history."

“WhatsApp is the first global messaging service at this scale to offer end-to-end encrypted messaging and backups, and getting there was a really hard technical challenge that required an entirely new framework for key storage and cloud storage across operating systems,” Facebook CEO Mark Zuckerberg said in a public statement. Users who will choose encrypted backups will be asked by the platform to save a 64-digit unique encryption key, or create a strong password that will be tied to the key.