Sherlocked Security – Next-Gen Firewall / IPS Tuning
Maximize Detection, Minimize Noise: Intelligent Tuning for Inline Threat Prevention
1. Statement of Work (SOW)
Service Name: Next-Gen Firewall (NGFW) & Intrusion Prevention System (IPS) Tuning
Client Type: Mid-to-Large Enterprises, MSSPs, Regulated Industries
Service Model: One-time Assessment & Tuning / Quarterly Optimization
Compliance Alignment: PCI-DSS, NIST 800-53, ISO 27001, MITRE ATT&CK
Platforms Covered:
- Palo Alto NGFW
- Cisco Firepower (FTD)
- Fortinet FortiGate
- Check Point
- Suricata/Snort-based IPS
- AWS/GCP/Azure NGFWs
2. Our Approach
[Policy Review] → [Signature Optimization] → [Threat Coverage Mapping] → [False Positive Suppression] → [Performance Balancing]
3. Methodology
-
Baseline Review of Policies
- Validate security zones and rule logic
- Detect redundant or shadowed rules
- Analyze rule hit count and usage
-
IPS/Threat Signature Audit
- Enable appropriate threat categories (e.g., malware, exploit kits, DNS abuse)
- Disable obsolete or low-relevance signatures
- Fine-tune severity, confidence, and action (alert/block/drop)
-
False Positive Analysis
- Identify noisy signatures
- Tune or suppress noisy alerts (by IP/user/app context)
- Whitelist legitimate apps generating false alerts
-
Threat Coverage Mapping
- Align enabled protections with MITRE ATT&CK TTPs
- Ensure coverage of ransomware, C2, phishing, lateral movement
-
Performance vs Security Balancing
- Profile impact of heavy signatures
- Adjust inspection profiles (e.g., by app group or zone)
- Utilize hardware acceleration or offloading where applicable
4. Deliverables
- Firewall/IPS Policy Optimization Report
- Signature Effectiveness & Coverage Matrix
- List of Suppressed/Disabled Signatures with Justification
- Tuning Change Log
- MITRE ATT&CK Coverage Map
- Post-Tuning Alert Volume Analysis
- Secure Profile Templates for Future Use
5. Client Requirements
- Access to NGFW/IPS console or management API
- Current security policy and signature configuration
- Logs of top alerts (last 30-60 days preferred)
- List of critical assets, zones, and business applications
- Performance constraints (if any)
6. Tools & Stack
- Platforms: Palo Alto Panorama, Firepower FMC, FortiManager
- Open Source: Suricata, Snort, Security Onion
- Analysis Tools: Elastic, Splunk, Wireshark, custom Python parsers
- MITRE ATT&CK Mapping: CALDERA, ATT&CK Navigator
- Automation: Ansible, API scripts
7. Engagement Lifecycle
- Initial Policy and Threat Review
- Alert & False Positive Profiling
- Signature Effectiveness Audit
- Tuning Plan & Impact Simulation
- Policy Updates & Tuning Rollout
- Post-Tuning Review & KPI Tracking
8. Why Sherlocked?
| Feature | Advantage |
|---|---|
| Deep Platform Expertise | Skilled in tuning top-tier NGFW/IPS vendors |
| ATT&CK-Based Tuning | Threat-informed defense with MITRE coverage mapping |
| Performance-Aware | Balance protection and throughput |
| Continuous Optimization | Available as quarterly managed service |
9. Tuning SOP Highlights
- Suppress benign alerts by IP, app, or zone
- Enable only relevant threat categories
- Log and justify every disabled signature
- Simulate changes in test/preprod when possible
- Review alert delta pre/post tuning
- Implement tuning rollback plans
- Align tuning with current threat landscape
10. Optimization Checklist
Before Engagement
- [ ] Export current IPS/firewall rules and signatures
- [ ] Provide alert logs and top talkers
- [ ] Identify critical assets and traffic paths
During Engagement
- [ ] Evaluate signature/action effectiveness
- [ ] Identify high-noise, low-value alerts
- [ ] Tune based on real-world behavior
After Engagement
- [ ] Review alert volume and incident response gain
- [ ] Apply secure tuning profiles to other zones
- [ ] Schedule recurring reviews (quarterly or after major upgrades)
Continuous Improvement
- [ ] Monitor threat landscape changes
- [ ] Integrate with SIEM for alert validation
- [ ] Test and deploy new signatures regularly