Trail of Bits introduces SequenceHash for secure multihashing
SequenceHash provides a hash-agnostic method for securely hashing multiple values together without the risks of simple concatenation.
Summary
Trail of Bits has released SequenceHash and SequenceMAC, two new cryptographic constructions designed to solve the 'multihashing' problem. Unlike NIST's TupleHash, which is tied to Keccak, SequenceHash works with various functions like SHA256, BLAKE, and RIPEMD. The project aims to prevent security vulnerabilities like ambiguous input encoding and length-extension attacks in applications like zero-knowledge proofs.
Technical features of SequenceHash
- Hash-agnostic design: Compatible with SHA256, SHA384, SHA512, BLAKE, and RIPEMD.
- Unambiguous encoding: Ensures inputs are semantically distinct to prevent mixing parts of different inputs.
- Length-extension prevention: Protects against attacks common in SHA2 family functions.
- Implementation availability: Initial versions released in Rust, Go, and Python.
- Standardization: The specification is part of the Community Cryptography Specification Project (C2SP).
Why it matters
By providing a standardized way to multihash across different algorithms, it reduces the risk of high-value forgeries in cryptocurrency and zero-knowledge proof protocols.
Original reference: blog.trailofbits.com →