modbender 🛡️ SkillGuard — ClawHub Security Scanner
"Trust, but verify."
ClawHub has no moderation process. Any agent can publish any skill. SkillGuard provides the security layer that's missing — scanning skills for dangerous patterns, vulnerable dependencies, and suspicious behaviors before they touch your system.
🚨 Why This Matters
Third-party skills can:
| Risk | Impact |
|---|---|
| Execute arbitrary code | Full system compromise |
| Access your filesystem | Data theft, ransomware |
| Read environment variables | API key theft ($$$) |
| Exfiltrate data via HTTP | Privacy breach |
| Install malicious dependencies | Supply chain attack |
| Persist backdoors | Long-term compromise |
| Escalate privileges | Root access |
One malicious skill = game over.
SkillGuard helps you catch threats before installation.
📦 Installation
clawhub install clawscan
Or manually:
git clone https://github.com/G0HEAD/skillguard
cd skillguard
chmod +x scripts/skillguard.py
Requirements
- Python 3.8+
clawhubCLI (for remote scanning)
🚀 Quick Start
# Scan a skill BEFORE installing
python3 scripts/skillguard.py scan some-random-skill
# Scan a local folder (your own skills or downloaded)
python3 scripts/skillguard.py scan-local ./path/to/skill
# Audit ALL your installed skills
python3 scripts/skillguard.py audit-installed
# Generate detailed security report
python3 scripts/skillguard.py report some-skill --format markdown
# Check dependencies for known vulnerabilities
python3 scripts/skillguard.py deps ./path/to/skill
🔍 What SkillGuard Detects
🔴 CRITICAL — Block Installation
These patterns indicate serious security risks:
| Category | Patterns | Risk |
|---|---|---|
| Code Execution | eval(), exec(), compile() |
Arbitrary code execution |
| Shell Injection | subprocess(shell=True), os.system(), os.popen() |
Command injection |
| Child Process | child_process.exec(), child_process.spawn() |
Shell access (Node.js) |
| Credential Theft | Access to ~/.ssh/, ~/.aws/, ~/.config/ |
Private key/credential theft |
| System Files | /etc/passwd, /etc/shadow |
System compromise |
| Recursive Delete | rm -rf, shutil.rmtree('/') |
Data destruction |
| Privilege Escalation | sudo, setuid, chmod 777 |
Root access |
| Reverse Shell | Socket + subprocess patterns | Remote access |
| Crypto Mining | Mining pool URLs, stratum:// |
Resource theft |
🟡 WARNING — Review Before Installing
These patterns may be legitimate but warrant inspection:
| Category | Patterns | Concern |
|---|---|---|
| Network Requests | requests.post(), fetch() POST |
Where is data going? |
| Environment Access | os.environ, process.env |
Which variables? |
| File Writes | open(..., 'w'), writeFile() |
What's being saved? |
| Base64 Encoding | base64.encode(), btoa() |
Obfuscated payloads? |
| External IPs | Hardcoded IP addresses | Exfiltration endpoints? |
| Bulk File Ops | shutil.copytree(), glob |
Mass data access? |
| Persistence | crontab, systemctl, .bashrc |
Auto-start on boot? |
| Package Install | pip install, npm install |
Supply chain risk |
🟢 INFO — Noted But Normal
| Category | Patterns | Note |
|---|---|---|
| File Reads | open(..., 'r'), readFile() |
Expected for skills |
| JSON Parsing | json.load(), JSON.parse() |
Data handling |
| Logging | print(), console.log() |
Debugging |
| Standard Imports | import os, import sys |
Common libraries |
📊 Scan Output Example
╔══════════════════════════════════════════════════════════════╗
║ 🛡️ SKILLGUARD SECURITY REPORT ║
╠══════════════════════════════════════════════════════════════╣
║ Skill: suspicious-helper v1.2.0 ║
║ Author: unknown-user ║
║ Files: 8 analyzed ║
║ Scan Time: 2024-02-03 05:30:00 UTC ║
╚══════════════════════════════════════════════════════════════╝
📁 FILES SCANNED
────────────────────────────────────────────────────────────────
✓ SKILL.md (541 bytes)
✓ scripts/main.py (2.3 KB)
✓ scripts/utils.py (1.1 KB)
✓ scripts/network.py (890 bytes)
✓ config.json (234 bytes)
✓ requirements.txt (89 bytes)
✓ package.json (312 bytes)
✓ install.sh (156 bytes)
🔴 CRITICAL ISSUES (3)
────────────────────────────────────────────────────────────────
[CRIT-001] scripts/main.py:45
│ Pattern: eval() with external input
│ Risk: Arbitrary code execution
│ Code: result = eval(user_input)
│
[CRIT-002] scripts/utils.py:23
│ Pattern: subprocess with shell=True
│ Risk: Command injection vulnerability
│ Code: subprocess.run(cmd, shell=True)
│
[CRIT-003] install.sh:12
│ Pattern: Recursive delete with variable
│ Risk: Potential data destruction
│ Code: rm -rf $TARGET_DIR/*
🟡 WARNINGS (5)
────────────────────────────────────────────────────────────────
[WARN-001] scripts/network.py:15 — HTTP POST to external URL
[WARN-002] scripts/main.py:78 — Reads OPENAI_API_KEY
[WARN-003] requirements.txt:3 — Unpinned dependency: requests
[WARN-004] scripts/utils.py:45 — Base64 encoding detected
[WARN-005] config.json — Hardcoded IP: 192.168.1.100
🟢 INFO (2)
────────────────────────────────────────────────────────────────
[INFO-001] scripts/main.py:10 — Standard file read operations
[INFO-002] requirements.txt — 3 dependencies declared
📦 DEPENDENCY ANALYSIS
────────────────────────────────────────────────────────────────
requirements.txt:
⚠️ requests (unpinned - specify version!)
✓ json (stdlib)
✓ pathlib (stdlib)
package.json:
⚠️ axios@0.21.0 (CVE-2021-3749 - upgrade to 0.21.2+)
════════════════════════════════════════════════════════════════
VERDICT: 🚫 DANGEROUS
════════════════════════════════════════════════════════════════
⛔ DO NOT INSTALL THIS SKILL
3 critical security issues found:
• Arbitrary code execution via eval()
• Command injection via shell=True
• Dangerous file deletion pattern
Manual code review required before any use.
════════════════════════════════════════════════════════════════
🎯 Commands Reference
scan <skill-name>
Fetch and scan a skill from ClawHub before installing.
skillguard scan cool-automation-skill
skillguard scan cool-automation-skill --verbose
skillguard scan cool-automation-skill --json > report.json
scan-local <path>
Scan a local skill directory.
skillguard scan-local ./my-skill
skillguard scan-local ~/downloads/untrusted-skill --strict
audit-installed
Scan all skills in your workspace.
skillguard audit-installed
skillguard audit-installed --fix # Attempt to fix issues
deps <path>
Analyze dependencies for known vulnerabilities.
skillguard deps ./skill-folder
skillguard deps ./skill-folder --update-db # Refresh vuln database
report <skill> [--format]
Generate detailed security report.
skillguard report suspicious-skill --format markdown > report.md
skillguard report suspicious-skill --format json > report.json
skillguard report suspicious-skill --format html > report.html
allowlist <skill>
Mark a skill as manually reviewed and trusted.
skillguard allowlist my-trusted-skill
skillguard allowlist --list # Show all trusted skills
skillguard allowlist --remove old-skill
watch
Monitor for new skill versions and auto-scan updates.
skillguard watch --interval 3600 # Check every hour
⚙️ Configuration
Create ~/.skillguard/config.json:
{
"severity_threshold": "warning",
"auto_scan_on_install": true,
"block_critical": true,
"trusted_authors": [
"official",
"PaxSwarm",
"verified-publisher"
],
"allowed_domains": [
"api.openai.com",
"api.anthropic.com",
"api.github.com",
"clawhub.ai"
],
"ignored_patterns": [
"test_*.py",
"*_test.js",
"*.spec.ts"
],
"custom_patterns": [
{
"regex": "my-internal-api\\.com",
"severity": "info",
"description": "Internal API endpoint"
}
],
"vuln_db_path": "~/.skillguard/vulns.json",
"report_format": "markdown",
"color_output": true
}
🔐 Security Levels
After scanning, skills are assigned a security level:
| Level | Badge | Meaning | Recommendation |
|---|---|---|---|
| Verified | ✅ | Trusted author, no issues | Safe to install |
| Clean | 🟢 | No issues found | Likely safe |
| Review | 🟡 | Warnings only | Read before installing |
| Suspicious | 🟠 | Multiple warnings | Careful review needed |
| Dangerous | 🔴 | Critical issues | Do not install |
| Malicious | ⛔ | Known malware patterns | Block & report |
🔄 Integration Workflows
Pre-Install Hook
# Add to your workflow
skillguard scan $SKILL && clawhub install $SKILL
CI/CD Pipeline
# GitHub Actions example
- name: Security Scan
run: |
pip install skillguard
skillguard scan-local ./my-skill --strict --exit-code
Automated Monitoring
# Cron job for daily audits
0 9 * * * /path/to/skillguard audit-installed --notify
📈 Vulnerability Database
SkillGuard maintains a local database of known vulnerabilities:
# Update vulnerability database
skillguard update-db
# Check database status
skillguard db-status
# Report a new vulnerability
skillguard report-vuln --skill bad-skill --details "Description..."
Sources:
- CVE Database (Python packages)
- npm Advisory Database
- GitHub Security Advisories
- Community reports
🚫 Limitations
SkillGuard is a first line of defense, not a guarantee:
| Limitation | Explanation |
|---|---|
| Obfuscation | Determined attackers can hide malicious code |
| Dynamic code | Runtime-generated code is harder to analyze |
| False positives | Legitimate code may trigger warnings |
| Zero-days | New attack patterns won't be detected |
| Dependencies | Deep transitive dependency scanning is limited |
Defense in depth: Use SkillGuard alongside:
- Sandboxed execution environments
- Network monitoring
- Regular audits
- Principle of least privilege
🤝 Contributing
Found a dangerous pattern we missed? Help improve SkillGuard:
Add a Pattern
{
"id": "CRIT-XXX",
"regex": "dangerous_function\\(",
"severity": "critical",
"category": "code_execution",
"description": "Dangerous function call",
"cwe": "CWE-94",
"remediation": "Use safe_alternative() instead",
"file_types": [".py", ".js"]
}
Report False Positives
skillguard report-fp --pattern "WARN-005" --reason "Legitimate use case"
📜 Changelog
v2.0.0 (Current)
- Comprehensive pattern database (50+ patterns)
- Dependency vulnerability scanning
- Multiple output formats (JSON, Markdown, HTML)
- Configuration file support
- Trusted author system
- Watch mode for monitoring updates
- Improved reporting with CWE references
v1.0.0
- Initial release
- Basic pattern detection
- Local and remote scanning
- Audit installed skills
📄 License
MIT License — Use freely, contribute back.
🛡️ Stay Safe
"In the agent ecosystem, trust is earned through transparency. Every skill you install is code you're choosing to run. Choose wisely. Verify always."
Built by PaxSwarm — protecting the swarm, one skill at a time 🐦⬛
Links: