hermes-dec

research

Reverse-engineering tool for React Native Hermes bytecode.

A decompiler and disassembler for Hermes bytecode, used to recover readable logic from React Native apps that ship compiled Hermes bundles.

hermes-dec decompiles and disassembles bytecode produced by the Hermes JavaScript engine used in React Native applications, helping analysts inspect mobile app logic that ships as compiled Hermes bundles instead of plain JavaScript.

What it does

• Parses Hermes bytecode files across multiple bytecode versions.
• Disassembles bytecode into a readable instruction listing.
• Decompiles bytecode back into pseudo-JavaScript for review.
• Supports both standalone .hbc files and bundles embedded inside Android/iOS app packages.

Best for

• Mobile security analysts reviewing React Native apps that ship Hermes bytecode.
• Researchers investigating obfuscated or non-source-available mobile clients.

Inputs: Hermes .hbc bytecode files, React Native app bundles

Outputs: Disassembled instruction listings, Decompiled pseudo-JavaScript