Detect slopsquatting attacks — AI-hallucinated packages registered by attackers in your dependencies.

Large Language Models regularly hallucinate package names that don't exist. Attackers register these names on npm and PyPI, turning every pip install or npm install from AI-generated code into a potential supply-chain attack.

A Trend Micro study found that 21 out of 126 AI-hallucinated package names had been registered on PyPI — some containing malicious code.

slopwatch scans your dependency files and scores each package with a trust model trained on real slopsquatting data. No dictionary of known-bad names: it uses statistical metadata analysis to detect suspicious packages regardless of whether they've been seen before.

Each package is scored from 0 to 100 using weighted metadata signals:

Severity thresholds:

• CRITICAL (score < 22): Very likely slopsquatting or malicious
• HIGH (score < 40): Suspicious, investigate manually
• MEDIUM (score < 60): Low metadata quality, worth checking
• OK (score >= 60): Appears legitimate

This model was validated at 100% F1 on a dataset of 81 packages (21 confirmed slopsquatting + 60 legitimate including hard negatives with low download counts).

Requires Rust 1.70+. Install via rustup or Homebrew:

# macOS
brew install rust

# All platforms
curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh

Then build:

cargo install --path .

Download from GitHub Releases:

# Linux x86_64
curl -L https://github.com/loicguillois/slopwatch/releases/latest/download/slopwatch-linux-x86_64 -o slopwatch
chmod +x slopwatch

slopwatch scan .

slopwatch auto-detects package.json, requirements.txt, and pyproject.toml.

slopwatch scan --file requirements.txt

# Colored terminal output (default)
slopwatch scan .

# JSON for programmatic use
slopwatch scan . --format json

# SARIF for GitHub/GitLab Security tab
slopwatch scan . --format sarif --output report.sarif

slopwatch — slopsquatting detector

  CRITICAL  wavesocket          (PyPI)   Score: 9.2/100
            ⚠ Very low downloads: 17/week
            ⚠ Very recent package: 8 days old
            ⚠ Only 1 version published
            ⚠ No description
            ⚠ No source repository linked
            ⚠ No license
            ⚠ No author information

  OK        requests            (PyPI)   Score: 82.5/100

─────────────────────────────────────────
Summary: 2 packages scanned
  CRITICAL: 1  |  OK: 1

Add slopwatch to your CI pipeline:

name: Security
on: [push, pull_request]

jobs:
  slopwatch:
    runs-on: ubuntu-latest
    permissions:
      security-events: write
    steps:
      - uses: actions/checkout@v4

      # Use full SHA for security (find latest at https://github.com/loicguillois/slopwatch/releases)
      - uses: loicguillois/slopwatch@COMMIT_SHA  # Replace with full SHA from releases
        with:
          path: "."
          format: "sarif"
          threshold: "22"
          fail-on-critical: "true"

When using sarif format, results are automatically uploaded to the Security tab of your GitHub repository.

# Run tests
cargo test

# Check formatting
cargo fmt --check

# Lint
cargo clippy -- -D warnings

Loïc Guillois — GitHub

MIT — see LICENSE