Apple recently unveiled PQ3, “the most significant cryptographic security upgrade in iMessage history”, for iOS 17.4 on February 21. With this new protocol, Apple becomes one of the few providers to offer post-quantum cryptography for messages.
Signal launched a “quantum attack-resistant” encryption upgrade in September 2023, but Apple claims to be the first to achieve “level 3” encryption. According to the Cupertino-based company: “PQ3 is the first messaging protocol to achieve what we call Level 3 security, offering protocol protections exceeding those of all other widely deployed messaging applications. To the best of our knowledge, PQ3 has the strongest security properties of any large-scale messaging protocol in the world.”
The Threat of Quantum Computers
Although Apple has always used end-to-end encryption for iMessage, the company switched from RSA encryption to elliptic curve cryptography (ECC) in 2019. Currently, breaking such an encryption is considered unfeasible due to the amount of time and computing power required. However, the threat of quantum computers is getting closer every day. Theoretically, a sufficiently powerful quantum computer could break current encryption methods with relative ease.
Preparing for the future
The big idea behind the early development of post-quantum cryptography methods is that good actors such as banks and hospitals can protect their data against malicious actors with access to cutting-edge technology. Unfortunately, bad actors don’t wait until they have access to a quantum computer to start their attacks. Many illicitly harvest encrypted data and store it for later decryption in what is commonly known as an HNDL (harvest now, decrypt later) attack.
Apple’s decision to introduce post-quantum cryptography in iMessage is an important step towards strengthening communications security. This initiative aims to anticipate technological advances and guarantee the protection of sensitive data against potential threats from quantum computers.
This transition to post-quantum cryptography demonstrates Apple’s commitment to staying ahead of potential threats and providing a secure communications environment for its users.
