pincer 🛡️
Security-first wrapper for clawhub install. Scans skills for malware, prompt injection, and suspicious patterns before installation.
Why?
Agent skills are powerful — they're basically executable documentation. The ClawHub ecosystem has already seen malware campaigns distributing infostealers via innocent-looking skills. pincer adds a security layer before you install anything.
Install
# From ClawHub
clawhub install pincer
# Or manually
chmod +x ./scripts/pincer.sh
ln -sf "$(pwd)/scripts/pincer.sh" ~/.local/bin/pincer
Dependencies:
clawhub— for fetching skillsuvx— for mcp-scan (brew install uv)jq— for JSON parsing
Usage
Safe Install
# Instead of: clawhub install some-skill
pincer install some-skill
# With specific version
pincer install some-skill@1.2.0
Scan Without Installing
# Scan a ClawHub skill
pincer scan some-skill
# Scan a local directory
pincer scan ./path/to/skill
# JSON output for automation
pincer scan some-skill --json
Audit Installed Skills
# Quick-scan all installed skills
pincer audit
# JSON output
pincer audit --json
Manage Trust
# Add trusted publisher (auto-approve clean skills)
pincer trust add steipete
# Remove from trusted
pincer trust remove old-publisher
# Block a publisher or skill
pincer trust block suspicious-dev
pincer trust block malware-skill
# Unblock
pincer trust unblock redeemed-dev
# List all trust settings
pincer trust list
View History
# See what you've installed
pincer history
# JSON output
pincer history --json
Configuration
# Show current config
pincer config show
# Edit in $EDITOR
pincer config edit
# Reset to defaults
pincer config reset
What It Checks
Via mcp-scan (Invariant Labs)
- Prompt injection attacks
- Malware payloads in natural language
- Tool poisoning
- Sensitive data exposure
- Hard-coded secrets
Additional Pattern Detection
| Pattern | Risk | Description |
|---|---|---|
| Base64 commands | 🚨 High | Encoded shell commands |
| Hex payloads | 🚨 High | Obfuscated binary data |
xattr -d quarantine |
🚨 High | macOS Gatekeeper bypass |
curl | sh |
🚨 High | Pipe to shell execution |
| Password archives | 🚨 High | Hidden malicious payloads |
| Download + execute | ⚠️ Medium | chmod +x && ./ patterns |
eval $var |
⚠️ Medium | Dynamic code execution |
| Hidden files | ⚠️ Medium | Dot-file creation |
| Persistence | ⚠️ Medium | cron/launchd entries |
Publisher & Provenance
- Publisher reputation (trusted list)
- Download count threshold
- Skill age threshold
- Blocklist checking
Binary Detection
- Scans for bundled executables
- Flags Mach-O, ELF, PE32 binaries
Risk Levels
| Level | Meaning | Action |
|---|---|---|
| ✅ CLEAN | No issues | Auto-approve if trusted publisher |
| ⚠️ CAUTION | Warnings present | Prompt for approval |
| 🚨 DANGER | Suspicious patterns | Block (override with --force) |
| ☠️ MALWARE | Known malicious | Block (cannot override) |
| ⛔ BLOCKED | On blocklist | Block (cannot override) |
Configuration
Config: ~/.config/pincer/config.json
{
"trustedPublishers": ["openclaw", "steipete", "invariantlabs-ai"],
"blockedPublishers": [],
"blockedSkills": [],
"autoApprove": "clean",
"logInstalls": true,
"minDownloads": 0,
"minAgeDays": 0
}
| Key | Description |
|---|---|
trustedPublishers |
Publishers whose clean skills auto-approve |
blockedPublishers |
Always block these publishers |
blockedSkills |
Always block these specific skills |
autoApprove |
"clean" = auto-approve clean+trusted, "never" = always prompt |
logInstalls |
Log installations to history file |
minDownloads |
Warn if skill has fewer downloads |
minAgeDays |
Warn if skill is newer than N days |
Examples
Clean Install
$ pincer install bird
🛡️ pincer v1.0.0
→ Fetching bird from ClawHub...
Publisher: steipete (trusted)
Stats: 7363 downloads · 27 ★ · created 1 month ago
🛡️ pincer Scanning bird...
→ Running mcp-scan...
✅ mcp-scan: passed
→ Checking for suspicious patterns...
✅ Pattern check: passed
→ Checking external URLs...
✅ URL check: passed
→ Checking for bundled binaries...
✅ Binary check: passed
Risk Assessment:
✅ CLEAN — No issues detected
→ Auto-approved (clean + trusted config).
→ Installing bird...
✅ Installed successfully!
Dangerous Skill Blocked
$ pincer install sketchy-tool
🛡️ pincer v1.0.0
→ Fetching sketchy-tool from ClawHub...
Publisher: newaccount (unknown)
Stats: 12 downloads · 0 ★ · created 2 days ago
🛡️ pincer Scanning sketchy-tool...
→ Running mcp-scan...
🚨 mcp-scan: high-risk warnings
→ Checking for suspicious patterns...
🚨 Pattern check: suspicious patterns found
• curl/wget piped to shell
• macOS quarantine removal (xattr)
→ Checking external URLs...
⚠️ URL check: external URLs found
• http://sketchy-domain.xyz/install
→ Checking for bundled binaries...
✅ Binary check: passed
Risk Assessment:
🚨 DANGER — Suspicious patterns detected
• mcp-scan: high-risk patterns detected
• curl/wget piped to shell
• macOS quarantine removal (xattr)
☠️ Install blocked. Use --force to override (not recommended).
Credits
- mcp-scan by Invariant Labs — core security scanning
- 1Password Security Research — threat analysis that inspired this tool
- Snyk ToxicSkills Report — ecosystem threat research
License
MIT
Stay safe out there. 🛡️