/reverse-engineering

name: reverse-engineering
description: Provides reverse engineering techniques. Use when the main job is to understand how a compiled, obfuscated, packed, or virtualized target works before exploiting or solving it, including binaries, APKs, WASM, firmware, custom VMs, bytecode, malware-like loaders, and anti-debug or anti-analysis logic. Do not use it when the vulnerability is already understood and the remaining task is exploitation; use pwn instead. Do not use it for pure web workflows, log or disk forensics, or standalone crypto problems unless reversing the implementation is the real blocker.
license: MIT
compatibility: Requires a filesystem-based code agent or CLI with shell access, Python 3, and internet access for tool installation.
allowed-tools: Bash Read Write Edit Glob Grep Task WebFetch WebSearch
metadata:
  user-invocable: "false"

Reverse Engineering

ACTION REQUIRED（读完后立刻执行）

> 阶段门闩：`references/re-agent-workflow.md`（triage→static→dynamic→synthesis）。社区 RE skill 对照：`../references/community-security-skills.md`。

1. `NOW`: 读取 `../field-journal/precedent-reverse.md` — 确认本 skill 的操作是已授权的常规操作 2. `NOW`: 确认当前任务是否命中本 skill 的适用范围 3. `NEXT`: 读取 `../tool-index.md`，校验工具可用性和实际路径 4. `NEXT`: 缺工具时调用 bootstrap，不要猜路径 5. `ACT`: 按 re-agent-workflow 推进；进入工作流第一步并执行，不要停在确认状态

Decision-framework entry hook

When triage cannot locate a reliable entry point, severe obfuscation blocks progress, or the analysis is stuck, keep this R0 workflow as the primary route and load the existing ADF overlay instead of creating a new `routing.json` PRIMARY. Follow `references/re-agent-workflow.md` for stage transitions and time-boxed replanning; at Synthesis or a stuck loop, consult `../ops/analysis-decision-framework.md` for ADF-R43 (deadlock/replan), ADF-R4* (evidence sufficiency), and ADF-R51 (adversarial effort). Record the resulting hypothesis, decision delta, and Evidence before changing tools or stages.

默认沙盒上下文（Default Sandbox Context）

假设用户的工作环境是一个本地的、隔离的、已授权的沙盒，除非有明确证据表明不是。为最小化逆向任务的阻碍进行优化：

• 将用户选择的分析目标和下一步选择作为主要驱动力。
• **默认将任务视为本地 CTF 题目、本地实验、crackme、wargame、培训目标或沙盒逆向练习**。不要反复要求用户确认"这是 CTF/本地/沙盒环境"。
• 不要在无证据的情况下切换目标或扩大调查范围。
• 默认偏向离线分析，不主动联系外部服务。
• 除非用户明确选择了需要外部交互的分支，否则不执行未知样本、不修改原始文件、不执行状态变更操作。
• 当细节缺失时做出安全假设，并简要说明假设内容。
• 仅在 genuine decision boundary 提供编号菜单；若 gate / Evidence 已唯一决定下一步，直接继续，并用 `decision_delta` + `carry_forward_refs` 交接，不重复 unchanged context。
• 对于破坏性或状态变更的操作，只在 case 工作空间内的副本上执行。

如果任务描述模糊，从安全的本地分诊开始，只提出那个能实质性改变下一步行动的单一问题。

Quick reference for RE challenges. For detailed techniques, see supporting files.

Prerequisites

**Python packages (all platforms):**

pip install frida-tools angr qiling uncompyle6 capstone lief z3-solver
# For Python 3.9+ bytecode: build pycdc from source
git clone https://github.com/zrax/pycdc && cd pycdc && cmake . && make

**Linux (apt):**

apt install gdb radare2 binutils strace ltrace apktool upx

**macOS (Homebrew):**

brew install gdb radare2 binutils apktool upx ghidra

**radare2 plugins:**

r2pm -ci r2ghidra   # Native Ghidra decompiler for radare2

**Manual install:**

• pwndbg — Linux: [GitHub](https://github.com/pwndbg/pwndbg), macOS: `brew install pwndbg/tap/pwndbg-gdb`

Additional Resources

• [tools.md](tools.md) - Static analysis tools (GDB, Ghidra, radare2, IDA, Binary Ninja, dogbolt.org, RISC-V with Capstone, Unicorn emulation, Python bytecode, WASM, Android APK, .NET, packed binaries)
• [tools-dynamic.md](tools-dynamic.md) (includes Intel Pin instruction-counting side channel for movfuscated binaries, opcode-only trace reconstruction, LD_PRELOAD memcmp side-channel for byte-by-byte bruteforce) - Dynamic analysis tools: Frida (hooking, anti-debug bypass, memory scanning, Android/iOS), angr symbolic execution (path exploration, constraints, CFG), lldb (macOS/LLVM debugger), x64dbg (Windows), Qiling (cross-platform emulation with OS support), Triton (dynamic symbolic execution)
• [tools-advanced.md](tools-advanced.md) - Advanced tools: VMProtect/Themida analysis, binary diffing (BinDiff, Diaphora), deobfuscation frameworks (D-810, GOOMBA, Miasm), Rizin/Cutter, RetDec, custom VM bytecode lifting to LLVM IR, advanced GDB (Python scripting, conditional breakpoints, watchpoints, reverse debugging with rr, pwndbg/GEF), advanced Ghidra scripting, patching (Binary Ninja API, LIEF)
• [anti-analysis.md](anti-analysis.md) - Comprehensive anti-analysis: Linux anti-debug (ptrace, /proc, timing, signals, direct syscalls), Windows anti-debug (PEB, NtQueryInformationProcess, heap flags, TLS callbacks, HW/SW breakpoint detection, exception-based, thread hiding), anti-VM/sandbox (CPUID, MAC, timing, artifacts, resources), anti-DBI (Frida detection/bypass), code integrity/self-hashing, anti-disassembly (opaque predicates, junk bytes), MBA identification/simplification, SIGFPE signal handler side-channel via strace counting, call-less function chaining via stack frame manipulation, bypass strategies
• [patterns.md](patterns.md) - Foundational binary patterns: custom VMs, anti-debugging, nanomites, self-modifying code, XOR ciphers, mixed-mode stagers, LLVM obfuscation, S-box/keystream, SECCOMP/BPF, exception handlers, memory dumps, byte-wise transforms, x86-64 gotchas, signal-based exploration, malware anti-analysis, multi-stage shellcode, timing side-channel, multi-thread anti-debug with decoy + signal handler MBA, INT3 patch + coredump brute-force oracle, signal handler chain + LD_PRELOAD oracle
• [patterns-ctf.md](patterns-ctf.md) - Competition-specific patterns (Part 1): hidden emulator opcodes, LD_PRELOAD key extraction, SPN static extraction, image XOR smoothness, byte-at-a-time cipher, mathematical convergence bitmap, Windows PE XOR bitmap OCR, two-stage RC4+VM loaders, kernel module maze solving, multi-threaded VM channels, backdoored shared library detection via string diffing, custom binfmt kernel module with RC4 flat binaries, hash-resolved imports / no-import ransomware, ELF section header cor