symbolic-execution - The Trail of Bits Blog

During my internship at Trail of Bits, I explored the effectiveness of symbolic execution for finding vulnerabilities in native applications ranging from CTF challenges to popular open source libraries like image parsers, focusing on finding ways to enhance ManticoreUI. It is a powerful tool that improves accessibility to symbolic execution and vulnerability […]

We have released Maat, a cross-architecture, multi-purpose, and user-friendly symbolic execution framework. It provides common symbolic execution capabilities such as dynamic symbolic execution (DSE), taint analysis, binary instrumentation, environment simulation, and constraint solving. Maat is easy-to-use, is based on the popular Ghidra intermediate representation (IR) language p-code, prioritizes runtime performance, and has […]

During my summer internship, I had the wonderful opportunity to work on the Manticore User Interface (MUI). The MUI project aims to combine the strength of both Manticore, a powerful symbolic execution library, and Binary Ninja, a popular binary analysis tool, to provide a more intuitive and visual interface […]

Smart contract authors can now express security properties in the same language they use to write their code (Solidity) and our new tool, manticore-verifier, will automatically verify those invariants. Even better, Echidna and Manticore share the same format for specifying property tests. In other words, smart contract authors can now write one property test and […]

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 […]

With the release of Manticore 0.3.3, we’re proud to announce support for symbolically executing WebAssembly (WASM) binaries. WASM is a newly standardized programming language that allows web developers to run code with near-native performance directly within the browser. Manticore 0.3.3 can explore all reachable states in a WASM program, and derive the concrete inputs that […]

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 […]

KLEE-Native, a fork of KLEE that operates on binary program snapshots by lifting machine code to LLVM bitcode.

If unit tests are important to you, there’s now another reason to use DeepState, our Google-Test-like property-based testing tool for C and C++. It’s called Eclipser, a powerful new fuzzer very recently presented in an ICSE 2019 paper. We are proud to announce that Eclipser is now fully integrated into DeepState. Eclipser provides many of […]

Each year, Trail of Bits runs a month-long winter internship “winternship” program. This year we were happy to host 4 winterns who contributed to 3 projects. This is the first in a series of blog posts covering the 2019 Wintern class. Our first report is from Vaibhav Sharma (@vbsharma), a PhD student at the University […]

Alex Groce, Associate Professor, School of Informatics, Computing and Cyber Systems, Northern Arizona University Mutation Testing Introducing one bug by hand (as we did in Part 1) is fine, and we could try it again, but “the plural of anecdote is not data.” However, this is not strictly true. If we have enough anecdotes, we […]

Alex Groce, Associate Professor, School of Informatics, Computing and Cyber Systems, Northern Arizona University Using DeepState, we took a handwritten red-black tree fuzzer and, with minimal effort, turned it into a much more fully featured test generator. The DeepState fuzzer, despite requiring no more coding effort, supports replay of regression tests, reduction of the size […]

Two years ago, when we began taking on blockchain security engagements, there were no tools engineered for the work. No static analyzers, fuzzers, or reverse engineering tools for Ethereum. So, we invested significant time and expertise to create what we needed, adapt what we already had, and refine the work continuously over dozens of audits. […]

Manticore is a next-generation binary analysis tool with a simple yet powerful API for symbolic execution, taint analysis, and instrumentation. Using Manticore one can identify ‘interesting’ code locations and deduce inputs that reach them. This can generate inputs for improved test coverage, or quickly lead execution to a vulnerability. I used Manticore’s power to solve Magic, a challenge […]

Manticore helps us quickly take advantage of symbolic execution, taint analysis, and instrumentation to analyze binaries.

Finding bugs in programs is hard. Automating the process is even harder. We tackled the harder problem and produced two production-quality bug-finding systems: GRR, a high-throughput fuzzer, and PySymEmu (PSE), a binary symbolic executor with support for concrete inputs. From afar, fuzzing is a dumb, brute-force method that works surprisingly well, and symbolic execution is […]

This is part two of a two-part blog post that shows how to use KLEE with mcsema to symbolically execute Linux binaries (see the first post!). This part will cover how to build KLEE, mcsema, and provide a detailed example of using them to symbolically execute an existing binary. The binary we’ll be symbolically executing […]

At THREADS 2014, I demonstrated a new capability of mcsema that enables the use of KLEE, a symbolic execution framework, on software available only in binary form. In the talk, I described how to use mcsema and KLEE to learn an unknown protocol defined in a binary that has never been seen before. In the example, […]