vm-and-bytecode-reverse

Analyze custom VM bytecode interpreters and reconstruct their ISA.

1.6k|204|Updated Apr 7, 2026

Search Tags:#bytecode #vm #ctf #reverse-engineering #disassembler #opcodes

Ready to run

npx skills add https://github.com/yaklang/hack-skills --skill vm-and-bytecode-reverse

💬 Prompt for ChatGPT / Claude Chat▼

Please help me install this Agent Skill.
Skill: vm-and-bytecode-reverse
Source: https://github.com/yaklang/hack-skills/tree/main/skills/vm-and-bytecode-reverse
Command: npx skills add https://github.com/yaklang/hack-skills --skill vm-and-bytecode-reverse

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve?

Analyzes and documents custom virtual machines and bytecode interpreters to enable rapid reverse-engineering workflows for challenges and protecting software.

Core Features & Use Cases

Identify and classify dispatcher types (switch, table, or indirect)
Map opcodes to operations, reconstruct ISA, and build a small disassembler
Apply to CTF challenges, malware analysis, and security research to reveal underlying logic

Quick Start

Provide a small bytecode sample and I will generate a readable disassembly and opcode map.

Frequently Asked Questions about vm-and-bytecode-reverse

High-intent search queries and answers about installing and using this skill.

FAQPage Schema

How do I reverse engineer custom VM bytecode for a CTF challenge?▼

To reverse engineer custom VM bytecode, you need to analyze the bytecode interpreter to identify dispatchers, map opcodes to operations, and reconstruct the instruction set architecture to generate a readable disassembly.

What is a bytecode dispatcher and how does it affect opcode extraction?▼

A bytecode dispatcher routes execution to opcode handlers and can be a switch statement, a dispatch table, or an indirect call. Identifying the dispatcher type is necessary to map opcodes and reconstruct the ISA accurately.

How do I build a disassembler for a custom instruction set architecture?▼

You build a disassembler for a custom ISA by providing a bytecode sample and any accompanying data to map opcodes to their underlying operations, generating a readable disassembly and opcode map.

Can I use bytecode reverse engineering for malware analysis?▼

Yes, bytecode reverse engineering applies to malware analysis and security research by documenting custom virtual machine interpreters to reveal underlying logic and reconstruct hidden operations.

What data do I need to provide to map custom VM opcodes?▼

You need to provide a VM bytecode sample and any accompanying data required to map opcodes, reconstruct the instruction set architecture, and generate a functional disassembler.