Posts

Specialized Zero-Knowledge Proof failures

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 […]

ABI compatibility in Python: How hard could it be?

TL;DR: Trail of Bits has developed abi3audit, a new Python tool for checking Python packages for CPython application binary interface (ABI) violations. We’ve used it to discover hundreds of inconsistently and incorrectly tagged package distributions, each of which is a potential source of crashes and exploitable memory corruption due to undetected ABI differences. It’s publicly […]

We’re streamers now

Trail of Bits
Over the years, we’ve built many high-impact tools that we use for security reviews. You might know some of them, like Slither, Echidna, Amarna, Tealer, and test-fuzz. All of our tools are open source, and we love seeing the community benefit from them. But mastering our tools takes time and practice, and it’s easier if […]

We sign code now

Sigstore announced the general availability of its free and ecosystem-agnostic software signing service two weeks ago, giving developers a way to sign, verify and protect their software projects and the dependencies they rely on. Trail of Bits is absolutely thrilled to be a part of the project, and we spoke about our […]

Stranger Strings: An exploitable flaw in SQLite

Andreas Kellas
Trail of Bits is publicly disclosing CVE-2022-35737, which affects applications that use the SQLite library API. CVE-2022-35737 was introduced in SQLite version 1.0.12 (released on October 17, 2000) and fixed in release 3.39.2 (released on July 21, 2022). CVE-2022-35737 is exploitable on 64-bit systems, and exploitability depends on how the program is […]

Secure your machine learning with Semgrep

tl;dr: Our publicly available Semgrep ruleset now has 11 rules dedicated to the misuse of machine learning libraries. Try it out now! Picture this: You’ve spent months curating images, trying out different architectures, downloading pretrained models, messing with Kubernetes, and you’re finally ready to ship your sparkling new machine learning (ML) product. […]

It pays to be Circomspect

Fredrik Dahlgren
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 […]

Magnifier: An Experiment with Interactive Decompilation

Today, we are releasing Magnifier, an experimental reverse engineering user interface I developed during my internship. Magnifier asks, “What if, as an alternative to taking handwritten notes, reverse engineering researchers could interactively reshape a decompiled program to reflect what they would normally record?” With Magnifier, the decompiled C code isn’t the end—it’s […]

Using mutants to improve Slither

Alex Groce, 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 […]

The road to the apprenticeship

Finding talent is hard, especially in the blockchain security industry. The space is new, so you won’t find engineers with decades of experience with smart contracts. Training is difficult, as the technology evolves constantly, and online content quickly becomes outdated. There are also a lot of misconceptions about blockchain […]

Shedding smart contract storage with Slither

Troy Sargent
You think you’ve found a critical bug in a Solidity smart contract that, if exploited, could drain a widely used cryptocurrency exchange’s funds. To confirm that it’s really a bug, you need to figure out the value at an obscure storage slot that has no getter method. Adrenaline courses […]

libmagic: The Blathering

Evan Sultanik
A couple of years ago we released PolyFile: a utility to identify and map the semantic structure of files, including polyglots, chimeras, and schizophrenic files. It’s a bit like file, binwalk, and Kaitai Struct all rolled into one. PolyFile initially used the TRiD definition database for file identification. However, […]