Google has announced a major security update for its Chrome web browser, moving from KYBER to ML-KEM (Module-Lattice-based Key-Encapsulation Mechanism) to protect against the risks posed by cryptographically relevant quantum computers (CRQCs). This transition is set to take effect with Chrome version 131, scheduled for release in early November 2024.
"Chrome will offer a key share prediction for hybrid ML-KEM (codepoint 0x11EC)," explained David Adrian, David Benjamin, Bob Beck, and Devon O'Brien of the Chrome Team. "The PostQuantumKeyAgreementEnabled flag and enterprise policy will apply to both Kyber and ML-KEM."
The shift away from KYBER was necessitated by incompatibility between the two hybrid post-quantum key exchange methods. Google's update will change the TLS codepoint from 0x6399 for Kyber768+X25519 to 0x11EC for ML-KEM768+X25519.
This move comes shortly after the U.S. National Institute of Standards and Technology (NIST) released three new encryption algorithms to secure current systems against future quantum-based attacks. These algorithms include ML-KEM (FIPS 203), CRYSTALS-Dilithium (ML-DSA, FIPS 204), and Sphincs+ (SLH-DSA, FIPS 205). Another algorithm, FN-DSA (formerly FALCON), is expected to be finalized later this year.
ML-KEM, derived from CRYSTALS-KYBER, is designed to establish secure key exchange over public channels, making it a key player in post-quantum cryptography (PQC).
In response to this quantum threat, Microsoft has also announced updates to its SymCrypt cryptographic library, which will support both ML-KEM and eXtended Merkle Signature Scheme (XMSS). Microsoft stated that the transition to post-quantum cryptography is a "complex, multi-year and iterative process" that requires careful planning.
Additionally, a cryptographic flaw, dubbed EUCLEAK (CVE-2024-45678), has been discovered in Infineon microcontrollers, affecting various YubiKey devices, including the YubiKey 5 Series. The flaw, which remained undetected for 14 years, could allow attackers to extract private keys from these hardware security tokens. However, physical access to the devices is required for the attack.
Yubico, the company behind YubiKey, has stated that due to security considerations, vulnerable devices cannot be updated. The company is now replacing Infineon's cryptographic library with its own in firmware versions YubiKey 5.7 and YubiHSM 2.4 to address the issue.
This discovery follows a similar side-channel attack on Google Titan security keys in 2021, further highlighting the need for robust and future-proof cryptographic measures in the face of evolving threats.
