Blockchain

Manticore discovers the ENS bug

The Ethereum Name Service (ENS) contract recently suffered from a critical bug that prompted a security advisory and a migration to a new contract (CVE-2020-5232). ENS allows users to associate online resources with human-readable names. As you might expect, it allows you to transfer and sell domain names. Specific details about the bug were in […]

Mainnet360: joint economic and security reviews with Prysm Group

Trail of Bits
On Monday, October 28th at the Crypto Economics Security Conference, Trail of Bits announced a new joint offering with Prysm Group: Mainnet360. Carefully designed to produce a comprehensive assessment of the security and economic elements of blockchain software, Mainnet360 gives teams a broader perspective that will allow them to build safer and more resilient systems. […]

Announcing the Crytic $10k Research Prize

Trail of Bits
At Trail of Bits, we make a significant effort to stay up to date with the academic world. We frequently evaluate our work through peer-reviewed conferences, and we love to attend academic events (see our recent ICSE and Crypto recaps). However, we consistently see one recurring issue at these academic events: a lack of reliable […]

Watch Your Language: Our First Vyper Audit

A lot of companies are working on Ethereum smart contracts, yet writing secure contracts remains a difficult task. You still have to avoid common pitfalls, compiler issues, and constantly check your code for recently discovered risks. A recurrent source of vulnerabilities comes from the early state of the programming languages available. Most developers are using […]

246 Findings From our Smart Contract Audits: An Executive Summary

Alex Groce
Until now, smart contract security researchers (and developers) have been frustrated by limited information about the actual flaws that survive serious development efforts. That limitation increases the risk of making critical smart contracts vulnerable, misallocating resources for risk reduction, and missing opportunities to employ automated analysis tools. We’re changing that. Today, Trail of Bits is […]

On LibraBFT’s use of broadcasts

Sam Moelius
LibraBFT is the Byzantine Fault Tolerant (BFT) consensus algorithm used by the recently released Libra cryptocurrency. LibraBFT is based on another BFT consensus algorithm called HotStuff. While some have noted the similarities between the two algorithms, they differ in some crucial respects. In this post we highlight one such difference: in LibraBFT, non-leaders perform broadcasts. […]

Avoiding Smart Contract “Gridlock” with Slither

Rajeev Gopalakrishna
A denial-of-service (DoS) vulnerability, dubbed ‘Gridlock,’ was publicly reported on July 1st in one of Edgeware’s smart contracts deployed on Ethereum. As much as $900 million worth of Ether may have been processed by this contract. Edgeware has since acknowledged and fixed the “fatal bug.” When we heard about Gridlock, we ran Slither on the […]

State of the Art Proof-of-Work: RandomX

Trail of Bits
RandomX is a new ASIC and GPU-resistant proof-of-work (PoW) algorithm originally developed for Monero, but potentially useful in any blockchain using PoW that wants to bias towards general purpose CPUs. Trail of Bits was contracted by Arweave to review this novel algorithm in a two person-week engagement and provide guidance on alternate parameter selection. But […]

Panicking the right way in Go

Sam Moelius
A common Go idiom is to (1) panic, (2) recover from the panic in a deferred function, and (3) continue on. In general, this is okay, so long there are no global state changes between the entry point to the function calling defer, and the point at which the panic occurs. Such global state changes […]

Slither: The Leading Static Analyzer for Smart Contracts

Gustavo Grieco
We have published an academic paper on Slither, our static analysis framework for smart contracts, in the International Workshop on Emerging Trends in Software Engineering for Blockchain (WETSEB), colocated with ICSE. Our paper shows that Slither’s bug detection outperforms other static analysis tools for finding issues in smart contracts in terms of speed, robustness, and […]

Empire Hacking: Ethereum Edition 2

Evan Sultanik
On December 12, over 150 attendees joined a special, half-day Empire Hacking to learn about pitfalls in smart contract security and how to avoid them. Thank you to everyone who came, to our superb speakers, and to BuzzFeed for hosting this meetup at their office. Watch the presentations again It’s hard to find such rich […]

10 Rules for the Secure Use of Cryptocurrency Hardware Wallets

Mike Myers
Earlier this year, the Web3 Foundation (W3F) commissioned Trail of Bits for a security review and assessment of the risks in storing cryptocurrency. Everyone who owns cryptocurrency — from large institutions to individual enthusiasts — shares the W3F’s concerns. In service to the broader community, the W3F encouraged us to publish our recommendations for the […]