How does Atheris compare to property-based testing like Hypothesis?

While Hypothesis uses schemas to generate data, Atheris uses code coverage feedback to intelligently mutate inputs, making it more effective at finding deep-seated bugs in complex logic.

Does Atheris support testing C extensions?

Yes, Atheris is specifically designed to handle Python C extensions and supports AddressSanitizer (ASan) to catch low-level memory corruption issues.

Why is a Docker environment recommended for Atheris?

Fuzzing C extensions requires specific versions of LLVM, Clang, and sanitizer libraries. A Docker environment ensures all these dependencies are correctly configured and isolated.

What is Atheris used for?

Atheris is used for coverage-guided fuzzing, which generates random inputs to test code paths in Python applications and C extensions to find crashes, memory leaks, and logic errors.

Atheris Python Fuzzer

Name: Atheris Python Fuzzer
Author: fjor1025

byfjor1025

0•

Security & Testing

Performs coverage-guided fuzz testing for pure Python code and C extensions to detect memory corruption and complex logic errors.

Atheris is a specialized Claude Code skill that provides a comprehensive framework for coverage-guided fuzzing in Python environments. By leveraging libFuzzer and AddressSanitizer (ASan), it allows developers to rigorously test both high-level Python logic and low-level C extensions for vulnerabilities like memory corruption, buffer overflows, and unhandled exceptions. This skill is essential for security-conscious developers building robust Python applications, offering detailed guidance on harness creation, corpus management, and containerized fuzzing workflows to ensure high-performance vulnerability discovery.

Key Features

010 GitHub stars

02Pre-configured Docker environment for consistent dependency management

03Seamless integration with libFuzzer's corpus management and minimization

04Integrated AddressSanitizer (ASan) support for memory corruption detection

05Coverage-guided fuzzing for pure Python and Python C extensions

06Automated code instrumentation using decorators and context managers

Use Cases

01Identifying edge-case logic bugs in complex Python libraries

02Security auditing of Python C extensions for memory safety vulnerabilities

03Stress-testing data parsers and protocols with randomized, feedback-driven inputs

What are Skills?·How to Install

Install with 🐟 Skill.Fish

npx skillfish add fjor1025/infosec-framework atheris

For use in Claude.ai and ChatGPT

Download Skill