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You can fuzz Python code by running a coverage-guided fuzzer that automatically generates diverse inputs to test execution paths. This approach leverages libFuzzer to discover bugs and memory corruption issues in pure Python code and native C extensions.

Yes, you can fuzz C extensions with built-in AddressSanitizer integration to detect memory errors. The fuzzer leverages ASan during automated input generation and execution to uncover native memory corruption issues within your C extensions.

Before fuzzing native C extensions, you need Python 3.7 or higher, clang, and specific environment variables configured for native extension fuzzing. These prerequisites enable libFuzzer and AddressSanitizer to properly instrument and analyze C code.

Coverage-guided fuzzing automatically explores code paths based on execution coverage. By generating diverse inputs and tracking which paths execute, the fuzzer systematically uncovers edge cases in Python parsing libraries that might lead to crashes or security exploits.

The best way to start fuzzing your Python application is to run the provided fuzzing script. This script initiates the coverage-guided fuzzing process to automatically generate inputs and test your code paths for vulnerabilities.