Apple iMessage encryption upgraded to protect breaches from quantum computers

Apple’s iMessage is super popular, with over a billion users chatting across the globe. But because it’s so big, it’s a big target for hackers. Even though quantum computers aren’t here yet, Apple’s probably getting ready just in case. That’s why iMessage’s security is getting a boost with post-quantum cryptography. It’ll be in iOS 17.4, iPadOS 17.4, macOS 14.4, and watchOS 10.4.

Apple’s latest blog post says they’ve created a post-quantum cryptographic protocol for iMessage called PQ3. It’ll keep the service safe from the toughest cyberattacks, and Apple thinks it’s better than any other messaging app’s security.

“Today we are announcing the most significant cryptographic security upgrade in iMessage history with the introduction of PQ3, a groundbreaking post-quantum cryptographic protocol that advances the state of the art of end-to-end secure messaging. With compromise-resilient encryption and extensive defenses against even highly sophisticated quantum attacks, PQ3 is the first messaging protocol to reach what we call Level 3 security — providing protocol protections that surpass those in all other widely deployed messaging apps. To our knowledge, PQ3 has the strongest security properties of any at-scale messaging protocol in the world.”

Most messaging services today use encryption with a public and private key. The public key encrypts messages, and the private key decrypts them. This all happens behind the scenes, as it should. The encryption is based on math functions, and a hacker’s ability to decrypt messages depends on the cipher and computing power. Quantum computers can handle this.

A powerful quantum computer can solve these math problems in new ways, which could be a problem for iMessage. But Apple says PQ3 will replace the current security protocol in all supported conversations later this year. To get this extra security, users need to make sure their devices have the latest software update.

As said earlier, quantum computers are still a few years off. But Apple thinks that someone with bad intentions could start gathering data now and decrypt it later when quantum computers are more common. To stay safe, Apple says encryption keys should keep changing. Their PQ3 protocol mixes the current encryption method for iMessage, called Elliptic-Curve cryptography, with post-quantum cryptography.

We can’t really tell how well Apple’s PQ3 standard works because there aren’t any quantum computers around to test it. Maybe in a few years, we’ll see how good it is. For now, we have to trust Apple’s word. If you want to know more about PQ3, you can read Apple’s research paper by clicking the source link below.