dotnet-reverse

A procedure for examining compiled .NET and C# programs to understand how they work. .NET assemblies are compiled program files such as managed EXE and DLL files.

In plain words
What is it for?
It helps analyze C# applications, red-team tools, protected or obfuscated programs, loaders, information stealers, and remote-access tools, including their decryption and command-and-control logic.
Why use it?
It provides a defined path from identifying a .NET file through deobfuscation, code inspection, debugging, and safe program changes.

Skill for Claude CodeCodex

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add skills/xamirhamza77/reverseops-skill/dotnet-reverse
Any agent
npx skills add xAmirHamza77/ReverseOps-Skill --skill dotnet-reverse
Clone the repo
git clone --depth 1 https://github.com/xAmirHamza77/ReverseOps-Skill

Made for: Claude Code, Codex.

Per session 132 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,734 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00132 $0.02734
Opus 5 $0.00066 $0.01367
Sonnet 5 $0.00026 $0.00547
Haiku 4.5 $0.00013 $0.00273

Measured 2d ago against content hash 7e1840930381, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

dotnet-reverse scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

skills/dotnet-reverse/SKILL.md · 193 lines

How it starts

The opening of the file, as written. The whole thing — 193 lines — stays where its author put it; the contents beside it link to each section on GitHub.

.NET / C# Reverse Engineering Standard Operating Procedure

ACTION REQUIRED (execute immediately after reading)

  1. NOW: Use DIE/file/CLR header to confirm the target is managed .NET (otherwise SWITCH to ida-reverse/ / reverse-engineering/)
  2. NOW: If obfuscation is suspected → run de4dot first to unpack, produce *-clean.exe, and preserve the original sample
  3. NEXT: Static analysis with dnSpyEx (or dnSpy MCP / ilspycmd): browse C# + use the IL view for key decision logic
  4. ACT: Debug dynamically when plaintext/C2 is needed; when logic changes are needed, prefer IL patching over C# recompilation
  5. At the end of each phase, give the user a 3–6 item next-step menu (including report export)

Scope

Prefer this skill when the task involves:

  • Identifying and reversing .NET / C# compiled artifacts (managed PE / .exe / .dll)
  • Analyzing red team Sharp* toolchains (Rubeus, SharpHound, SharpShell, etc.)
  • Deobfuscating ConfuserEx / SmartAssembly / Babel / Eazfuscator / .NET Reactor and similar protectors
  • Reversing the decryption and C2 logic of .NET loaders / info-stealers / RATs
  • Patching C# programs (modifying checks, constants, keygen)
  • Analyzing the pre-IL2CPP Mono/Unity managed layer (note: after IL2CPP compilation it is native; use reverse-engineering/ + seed-014)

If the target is a pure native binary (compiled C/C++/Go/Rust, no CLR), use reverse-engineering/, ida-reverse/, or radare2/ instead.

Core Principles

  • Identify before acting: Confirm it is a managed .NET program first (CLR in the PE header + #~ / #Strings streams + mscoree _CorExeMain), then decide to use dnSpy instead of IDA
  • IL over C#: dnSpyEx's C# decompiler can lose/distort information (compiler-generated state machines, async/await, yield); key decision logic and patches must be done in the IL editor. The C# view is only for quick browsing
  • de4dot first: When an obfuscator is encountered, run de4dot first before static analysis; otherwise strings/control flow are all garbage
  • MCP integration: If a dnSpy MCP (dnspy_* tools) is registered in the environment, prefer the MCP interface for decompilation / IL inspection to avoid switching back and forth to the GUI
  • Evidence-based output: Deobfuscated artifacts, extracted configs/C2/keys, and patch diffs must all be written to disk

Read the full file on GitHub · 193 lines

Files

What ships with it

3 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 2d ago First seen · 193 lines · 132 tokens per session scan A 7e1840930381

Subscribe to this mod's changes

dotnet-reverse is a skill published in the GitHub repository xAmirHamza77/ReverseOps-Skill (4 stars, last pushed 1mo ago), licensed MIT. It adds 132 tokens to every session and 2,734 once invoked, about $0.0007 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.