Opal Wright

Two popular AES libraries (aes-js and pyaes) provide dangerous default IVs that lead to key/IV reuse vulnerabilities affecting thousands of projects. One maintainer dismissed the issue, while strongSwan’s maintainer exemplified proper security response by comprehensively fixing the vulnerability in their VPN management tool.

Among the cryptographic missteps we see at Trail of Bits, “let’s build our own tool out of a hash function” is one of the most common. Clients have a problem along the lines of “we need to hash a bunch of different values together” or “we need a MAC” or “we need […]

You might be hearing a lot about post-quantum (PQ) cryptography lately, and it’s easy to wonder why it’s such a big deal when nobody has actually seen a quantum computer. But even if a quantum computer is never built, new PQ standards are safer, more resilient, and more flexible than their classical […]

The Fiat-Shamir transform is an important building block in zero-knowledge proofs (ZKPs) and multi-party computation (MPC). It allows zero-knowledge proofs based on interactive protocols to be made non-interactive. Essentially, it turns conversations into documents. This ability is at the core of powerful technologies like SNARKs and STARKs. Useful stuff! But the Fiat-Shamir […]

Zero-knowledge (ZK) proofs are useful cryptographic tools that have seen an explosion of interest in recent years, largely due to their applications to cryptocurrency. The fundamental idea of a ZK proof is that a person with a secret piece of information (a cryptographic key, for instance) can prove something about the secret […]