Exploring Verifiable Random Functions in Code

Verifiable Random Functions (VRFs) have recently seen a strong surge in popularity due to their usefulness in blockchain applications. Earlier I wrote about what VRFs are, where they can be used, and a few dozen things to consider when reviewing them. In this follow-on blog post, I am pleased to introduce actual working code that … Continue reading Exploring Verifiable Random Functions in Code

Whitepaper – Coinbugs: Enumerating Common Blockchain Implementation-Level Vulnerabilities

By Aleksandar Kircanski and Terence Tarvis A good amount of effort has been dedicated to surveying and systematizing Ethereum smart contract security bug classes. There is, however, a gap in literature when it comes to surveying implementation-level security bugs that commonly occur in basic PoW blockchain node implementations, discovered during the first decade of Bitcoin’s … Continue reading Whitepaper – Coinbugs: Enumerating Common Blockchain Implementation-Level Vulnerabilities

Public Report – RustCrypto AES/GCM and ChaCha20+Poly1305 Implementation Review

In December 2019, MobileCoin engaged NCC Group to conduct a review of the AES/GCM and ChaCha20+Poly1305 implementations provided by the RustCrypto/AEADs crates. The intended usage context of these crates includes SGX enclaves, making timing-related side channel attacks relevant to this assessment. Two consultants provided five person-days of effort. The Public Report for this audit may … Continue reading Public Report – RustCrypto AES/GCM and ChaCha20+Poly1305 Implementation Review

Reviewing Verifiable Random Functions

While Verifiable Random Functions (VRFs) were first described just over twenty years ago [1], they have recently seen a strong resurgence in popularity due to their usefulness in blockchain applications [2]. This blog post will introduce VRFs in the context of other well-known cryptographic primitives, describe three example use cases, and then highlight over two … Continue reading Reviewing Verifiable Random Functions