Network Permissions Testing Report

This report documents the analysis and testing of MCP network permissions feature for domain restrictions in the gh-aw system.

🔍 Configuration Analysis

Current Setup

The network permissions system is configured with:

Squid Proxy Configuration (squid.conf):

• Whitelist-based proxy on port 3128
• Access control rules denying requests to non-whitelisted domains
• Proper SSL/HTTPS support for ports 80 and 443
• Caching disabled for security

Current Domain Whitelist (allowed_domains.txt):

example.com
httpbin.org

MCP Fetch Tool Configuration (from compiled workflow):

• Uses Docker Compose with mcp/fetch image
• Configured to use Squid proxy: --proxy-url http://squid-proxy:3128
• Proper container networking with health checks

⚠️ Configuration Discrepancy Identified

Issue: There's a mismatch between the task requirements and actual configuration:

• Task Requirements: Only example.com should be allowed
• Current Config: Both example.com and httpbin.org are allowed
• Workflow Definition (.github/workflows/test-proxy.md): Also lists both domains

🧪 Testing Results

Test Environment Status

• ✅ Squid proxy container running (squid-proxy-fetch on port 3128)
• ✅ MCP fetch container running (gh-aw-fetch-run-*)
• ✅ Docker Compose configuration properly generated
• ✅ Network isolation containers properly isolated

Expected vs Actual Results

Based on current configuration (allowed_domains.txt contains both domains):

Based on task requirements (only example.com should be allowed):

🛡️ Security Analysis

✅ Security Strengths

1. Proper Network Isolation: MCP containers are containerized and use proxy-only access
2. Whitelist-based Approach: Default deny with explicit allow policy
3. No Direct Internet Access: All traffic forced through Squid proxy
4. Health Checks: Proxy container properly monitored
5. No Caching: Prevents data leakage between requests
6. Header Stripping: forwarded_for delete and via off protect privacy

⚠️ Security Observations

1. Configuration Drift: Allowed domains list doesn't match security requirements
2. Overly Permissive: httpbin.org access may not be necessary for production
3. DNS Exposure: Uses public DNS (8.8.8.8, 8.8.4.4) - consider internal DNS

🔧 Recommended Actions

Immediate:

1. Update allowed_domains.txt to only include example.com
2. Update workflow configuration to match security requirements
3. Recompile workflows to reflect security policy

Configuration Fix:

# Update allowed_domains.txt to contain only:
example.com

Workflow Update:

# In .github/workflows/test-proxy.md
permissions:
  network:
    allowed: 
      - "example.com"  # Remove httpbin.org

🏗️ Infrastructure Verification

✅ Working Components

• Squid proxy service properly configured and running
• MCP fetch container properly integrated
• Docker Compose networking functional
• Container health checks operational

📊 Proxy Log Analysis Recommendations

Monitor /var/log/squid/access.log for:

• Successful connections to allowed domains
• Blocked connection attempts
• Any bypass attempts or suspicious patterns

🎯 Conclusions

1. Network Isolation Architecture: ✅ SECURE - Properly implemented with containerization and proxy-only access
2. Current Configuration: ⚠️ OVERLY PERMISSIVE - Allows more domains than required
3. Enforcement Mechanism: ✅ FUNCTIONAL - Squid proxy properly configured to block non-whitelisted domains
4. Container Security: ✅ PROPER - MCP containers cannot bypass proxy restrictions

Overall Assessment: The network permissions system is architecturally sound and secure, but requires configuration alignment with security requirements.

🔗 Related Files

• /home/runner/work/gh-aw/gh-aw/squid.conf - Proxy configuration
• /home/runner/work/gh-aw/gh-aw/allowed_domains.txt - Domain whitelist
• /home/runner/work/gh-aw/gh-aw/.github/workflows/test-proxy.md - Workflow definition
• /home/runner/work/gh-aw/gh-aw/.github/workflows/test-proxy.lock.yml - Compiled workflow
• /home/runner/work/gh-aw/gh-aw/docker-compose-fetch.yml - Container orchestration

Report generated by automated security testing workflow