blockchain

Circomspect has been integrated into the Sindri CLI

Our tool Circomspect is now integrated into the Sindri command-line interface (CLI)! We designed Circomspect to help developers build Circom circuits more securely, particularly given the limited tooling support available for this novel programming framework. Integrating this tool into a development environment like that provided by Sindri is a significant step toward […]

Improving the state of Cosmos fuzzing

Cosmos is a platform enabling the creation of blockchains in Go (or other languages). Its reference implementation, Cosmos SDK, leverages strong fuzz testing extensively, following two approaches: smart fuzzing for low-level code, and dumb fuzzing for high-level simulation. In this blog post, we explain the differences between these approaches and show how […]

Celebrating our 2023 open-source contributions

At Trail of Bits, we pride ourselves on making our best tools open source, such as Slither, PolyTracker, and RPC Investigator. But while this post is about open source, it’s not about our tools… In 2023, our employees submitted over 450 pull requests (PRs) that were merged into non-Trail of Bits repositories. This demonstrates our […]

Billion times emptiness

Behind Ethereum’s powerful blockchain technology lies a lesser-known challenge that blockchain developers face: the intricacies of writing robust Ethereum ABI (Application Binary Interface) parsers. Ethereum’s ABI is critical to the blockchain’s infrastructure, enabling seamless interactions between smart contracts and external applications. The complexity of data types and the need for precise encoding […]

Introducing invariant development as a service

Understanding and rigorously testing system invariants are essential aspects of developing robust smart contracts. Invariants are facts about the protocol that should remain true no matter what happens. Defining and testing these invariants allows developers to prevent the introduction of bugs and make their code more robust in the long term. However, it is difficult […]

Can you pass the Rekt test?

One of the biggest challenges for blockchain developers is objectively assessing their security posture and measuring how it progresses. To address this issue, a working group of Web3 security experts, led by Trail of Bits CEO Dan Guido, met earlier this year to create a simple test for profiling the security of blockchain teams. We […]

A mistake in the bulletproofs paper could have led to the theft of millions of dollars

We discovered a critical vulnerability in Incognito Chain that would allow an attacker to mint arbitrary tokens and drain user funds. Incognito offers confidential transactions through zero-knowledge proofs, so an attacker could have stolen millions of dollars of shielded funds without ever being detected or identified. The vulnerability stemmed from an insecure […]

Evaluating blockchain security maturity

Holistic security reviews should reveal far more than simple bugs. Often, these bugs indicate deeper issues that can be challenging to understand and address. Given the time-boxed nature of reviews, security engineers may not have the opportunity to identify all bugs caused by these problems—and they may continue to […]

What we told the CFTC about blockchain threats

In March, I joined the Commodity Futures Trading Commission’s Technology Advisory Committee (TAC), helping the regulatory agency navigate the complexities of cybersecurity risks, particularly in emerging technologies like AI and blockchain. During the committee’s first meeting, I discussed how the rapidly changing and public nature of blockchain technology makes it uniquely susceptible […]

What should governments consider when getting involved with blockchain?

Last September, Principal Security Engineer Dr. Evan Sultanik was on a panel hosted by the Naval Postgraduate School’s Distributed Consensus: Blockchain & Beyond (DC:BB) movement, where faculty and students there are seeking opportunities to learn and share knowledge, research, funding, and events focused on distributed consensus technologies. The panel of nine government, academia, and industry […]

Circomspect has more passes!

TL;DR: We have released version 0.8.0 of Circomspect, our static analyzer and linter for Circom. Since our initial release of Circomspect in September 2022, we have added five new analysis passes, support for tags, tuples, and anonymous components, links to in-depth descriptions of each identified issue, and squashed a […]

Reusable properties for Ethereum contracts

As smart contract security constantly evolves, property-based fuzzing has become a go-to technique for developers and security engineers. This technique relies on the creation of code properties – often called invariants – which describe what the code is supposed to do. To help the community define properties, we are releasing a set of 168 pre-built […]

Hybrid fuzzing: Sharpening the spikes of Echidna

(University of Queensland, Australia)
Smart contract fuzzing is an effective bug-finding technique that is largely used at Trail Of Bits during audits. During my internship at Trail of Bits, I contributed to expand our fuzzing capabilities by working on Hybrid Echidna, a “hybrid fuzzer” that couples our smart contract fuzzer, Echidna, with […]

It pays to be Circomspect

In October 2019, a security researcher found a devastating vulnerability in Tornado.cash, a decentralized, non-custodial mixer on the Ethereum network. Tornado.cash uses zero-knowledge proofs (ZKPs) to allow its users to privately deposit and withdraw funds. The proofs are supposed to guarantee that each withdrawal can be matched against a […]

Using mutants to improve Slither

(Northern Arizona University)
Improving static analysis tools can be hard; once you’ve implemented a good tool based on a useful representation of a program and added a large number of rules to detect problems, how do you further enhance the tool’s bug-finding power? One (necessary) approach to coming up with new rules […]

Managing risk in blockchain deployments

Do you need a blockchain? And if so, what kind? Trail of Bits has released an operational risk assessment report on blockchain technology. As more businesses consider the innovative advantages of blockchains and, more generally, distributed ledger technologies (DLT), executives must decide whether and how to adopt them. Organizations adopting these systems must understand and […]

Are blockchains decentralized?

A new Trail of Bits research report examines unintended centralities in distributed ledgers Blockchains can help push the boundaries of current technology in useful ways. However, to make good risk decisions involving exciting and innovative technologies, people need demonstrable facts that are arrived at through reproducible methods and open data. We believe the risks inherent […]