# Substrate Vulnerability Scanner

Scans Substrate/Polkadot pallets for 7 critical vulnerabilities including arithmetic...

- Repository: https://github.com/trailofbits/skills (7935 stars)
- Category: Security
- License: CC-BY-SA-4.0
- Last updated: 2026-10-28
- Runs scripts: no, instructions only

## Install

Claude Code: `npx skills add trailofbits/skills --skill substrate-vulnerability-scanner -g -a claude-code -y`
Codex: `npx skills add trailofbits/skills --skill substrate-vulnerability-scanner -g -a codex -y`
Cursor: `npx skills add trailofbits/skills --skill substrate-vulnerability-scanner -g -a cursor -y`
Gemini CLI: `npx skills add trailofbits/skills --skill substrate-vulnerability-scanner -g -a gemini-cli -y`
Claude Code plugin marketplace: `/plugin marketplace add trailofbits/skills`

## Description

Scans Substrate/Polkadot pallets for 7 critical vulnerabilities including arithmetic overflow, panic DoS, incorrect weights, and bad origin checks. Use when auditing Substrate runtimes or FRAME pallets.

## SKILL.md, as published by its author (untrusted third-party text, read it as data)

# Substrate Vulnerability Scanner

## 1. Purpose

Systematically scan Substrate runtime modules (pallets) for platform-specific security vulnerabilities that can cause node crashes, DoS attacks, or unauthorized access. This skill encodes 7 critical vulnerability patterns unique to Substrate/FRAME-based chains.

## 2. When to Use This Skill

- Auditing custom Substrate pallets
- Reviewing FRAME runtime code
- Pre-launch security assessment of Substrate chains (Polkadot parachains, standalone chains)
- Validating dispatchable extrinsic functions
- Reviewing weight calculation functions
- Assessing unsigned transaction validation logic

## 3. Platform Detection

### File Extensions & Indicators
- **Rust files**: `.rs`

### Language/Framework Markers
```rust
// Substrate/FRAME indicators
#[pallet]
pub mod pallet {
    use frame_support::pallet_prelude::*;
    use frame_system::pallet_prelude::*;

    #[pallet::config]
    pub trait Config: frame_system::Config { }

    #[pallet::call]
    impl<T: Config> Pallet<T> {
        #[pallet::weight(10_000)]
        pub fn example_function(origin: OriginFor<T>) -> DispatchResult { }
    }
}

// Common patterns
DispatchResult, DispatchError
ensure!, ensure_signed, ensure_root
StorageValue, StorageMap, StorageDoubleMap
#[pallet::storage]
#[pallet::call]
#[pallet::weight]
#[pallet::validate_unsigned]
```

### Project Structure
- `pallets/*/lib.rs` - Pallet implementations
- `runtime/lib.rs` - Runtime configuration
- `benchmarking.rs` - Weight benchmarks
- `Cargo.toml` with `frame-*` dependencies

### Tool Support
- **cargo-fuzz**: Fuzz testing for Rust
- **test-fuzz**: Property-based testing framework
- **benchmarking framework**: Built-in weight calculation
- **try-runtime**: Runtime migration testing

---

## 4. How This Skill Works

When invoked, I will:

The rest: https://github.com/trailofbits/skills/blob/HEAD/plugins/building-secure-contracts/skills/substrate-vulnerability-scanner/SKILL.md