Yoder Skill Auditor

---
name: skill-auditor
version: 3.1.0
description: "The definitive security scanner for OpenClaw skills. 18 security checks including prompt injection detection, download-and-execute, privilege escalation, credential harvesting, supply chain attacks, crypto drains, and more. 5-dimension trust scoring with trend tracking."
metadata:
  openclaw:
    requires:
      bins: ["python3", "bash"]
      env: []
      config: []
    user-invocable: true
---

# Skill Auditor v3.1.0

The definitive security scanner for OpenClaw/ClawHub skills. Best-in-class detection across 18 security checks including **prompt injection detection** — the first scanner to catch agent manipulation attacks in skill documentation. 5-dimension trust scoring, trend tracking, diff analysis, and benchmarking. Zero false positives on legitimate skills.

## When to Activate

1. **Installing a new skill** from ClawHub - run `inspect.sh` for full pre-install validation
2. **Auditing existing skills** - use `audit.sh` to scan any skill directory
3. **Generating trust scores** - use `trust_score.py` for 0-100 rating across 5 dimensions
4. **Comparing skills** - use `trust_score.py --compare` for side-by-side analysis
5. **Tracking improvements** - use `trust_score.py --save-trend` to monitor score over time
6. **Reviewing updates** - use `diff-audit.sh` to compare before/after versions
7. **Batch scanning** - use `audit-all.sh` or `benchmark.sh` for fleet-wide analysis

## Quick Start

```bash
# Audit a single skill
bash audit.sh /path/to/skill

# Trust score (0-100 across 5 dimensions)
python3 trust_score.py /path/to/skill

# Compare two skills side by side
python3 trust_score.py /path/to/skill1 --compare /path/to/skill2

# Track score over time
python3 trust_score.py /path/to/skill --save-trend
python3 trust_score.py /path/to/skill --trend

# Diff audit (before/after update)
bash diff-audit.sh /path/to/old-version /path/to/new-version

# Benchmark against a corpus
bash benchmark.sh /path/to/skills-dir

# Inspect a ClawHub skill before installing
bash inspect.sh skill-slug

# Audit all installed skills
bash audit-all.sh

# Generate a markdown report
bash report.sh

# Run test suite (28 assertions)
bash test.sh
```

## Guardrails / Anti-Patterns

**DO:**
- ✓ Always audit skills before installing from untrusted sources
- ✓ Review trust scores - reject skills scoring below 60 (D grade)
- ✓ Use `diff-audit.sh` when updating skills to catch regressions
- ✓ Use `--json` output for CI/CD pipeline integration
- ✓ Run `--save-trend` periodically to track skill health

**DON'T:**
- ✗ Install skills scoring below 40 (F grade) without extensive manual review
- ✗ Ignore CRITICAL findings - they indicate potential security threats
- ✗ Blindly add skills to allowlist without understanding why they access credentials
- ✗ Skip audit because a skill is "popular" or "official"

## Security Checks (18 total)

| # | Check | Severity | Description |
|---|-------|----------|-------------|
| 1 | credential-harvest | CRITICAL | Scripts reading API keys/tokens AND making network calls |
| 2 | exfiltration-url | CRITICAL | webhook.site, requestbin, ngrok URLs in scripts |
| 3 | obfuscated-payload | CRITICAL | Base64-encoded URLs or shell commands |
| 4 | sensitive-fs | CRITICAL | /etc/passwd, ~/.ssh, ~/.aws/credentials access |
| 5 | crypto-wallet | CRITICAL | Hardcoded ETH/BTC wallet addresses (drain attacks) |
| 6 | dependency-confusion | CRITICAL | Internal/private-scoped packages in public deps |
| 7 | typosquatting | CRITICAL | Misspelled package names (lodahs, requets, etc.) |
| 8 | symlink-attack | CRITICAL | Symlinks targeting sensitive system paths |
| 9 | code-execution | WARNING | eval(), exec(), subprocess patterns |
| 10 | time-bomb | WARNING | Date/time comparisons that could trigger delayed payloads |
| 11 | telemetry-detected | WARNING | Analytics SDKs, tracking pixels, phone-home behavior |
| 12 | excessive-permissions | WARNING | >15 bins/env/config items requested |
| 13 | unusual-ports | WARNING | Network calls to non-standard ports |
| 14 | prompt-injection | CRITICAL | Agent manipulation in docs: "ignore instructions", role hijacking, hidden HTML directives |
| 15 | download-execute | CRITICAL | curl\|bash, wget\|sh, eval $(curl), unsafe pip/npm installs |
| 16 | hidden-file | WARNING | Suspicious dotfiles that may hide malicious content |
| 17 | env-exfiltration | CRITICAL | Reading sensitive env vars + outbound network calls |
| 18 | privilege-escalation | CRITICAL | sudo, chmod 777/setuid, writes to system paths |

Context-aware: credential mentions in documentation are INFO, not CRITICAL.

## Trust Score (5 Dimensions)

| Dimension | Max | What's Measured |
|-----------|-----|-----------------|
| Security | 35 | Audit findings (criticals = -18, warnings = -4) |
| Quality | 22 | Description, version, usage docs, examples, metadata, changelog |
| Structure | 18 | File organization, tests, README, reasonable scope |
| Transparency | 15 | License, no minified code, code comments |
| Behavioral | 10 | Rate limiting, error handling, input validation |

Grades: A (90+), B (75+), C (60+), D (40+), F (<40)

### Comparative Scoring
```bash
python3 trust_score.py /path/to/skill-a --compare /path/to/skill-b
```
Shows per-dimension deltas and overall score difference.

### Trend Tracking
```bash
python3 trust_score.py /path/to/skill --save-trend   # Record score
python3 trust_score.py /path/to/skill --trend         # View history
```
Stores up to 50 entries per skill in `trust_trends.json`.

## Tools

| File | Purpose |
|------|---------|
| audit.sh | Single skill security audit (18 checks) |
| audit-all.sh | Batch scan all installed skills |
| trust_score.py | Trust score calculator (5-dimension, 0-100) |
| diff-audit.sh | Compare skill versions for security regressions |
| benchmark.sh | Corpus-wide audit with aggregate statistics |
| inspect.sh | ClawHub pre-install workflow |
| report.sh | Markdown report generator |
| test.sh | Automated test suite (28 assertions, 12 test skills) |
| allowlist.json | Known-good credential skills |

## Test Suite

12 test skills (8 malicious, 4 clean) with 28 automated assertions:

```bash
bash test.sh
```

Malicious fixtures: credential harvest, obfuscated payload, sensitive fs reads, crypto wallets, time bombs, symlink attacks, prompt injection, download-execute, privilege escalation.
Clean fixtures: basic skill, credential docs (false positive check), network skill, dotfiles skill.

## Exit Codes
- 0: PASS / safe to install
- 1: REVIEW / warnings found
- 2: FAIL / critical issues
- 3: Error / bad input

## Changelog

See [CHANGELOG.md](CHANGELOG.md) for full version history.