Five Critical Controls
The SANS ICS 5 Critical Controls provide a proven framework for protecting industrial control systems from cyber threats. These ICS critical controls were developed by SANS cybersecurity experts through analysis of real-world attacks, offering prioritized guidance for implementing essential OT security controls in industrial environments.
Start with Critical Control #1 by developing ICS-specific incident response plans, then build a defensible architecture, implement network monitoring for continuous visibility, establish secure remote access, and finally develop vulnerability management programs tailored to industrial environments and operational constraints.
The SANS critical controls are important because they were developed through analysis of actual ICS cyber attacks, focus on the highest-impact security measures, provide prioritized implementation guidance, and address the unique challenges of protecting operational technology while maintaining safety and operational requirements.
Unlike generic IT security frameworks, the SANS ICS 5 Critical Controls are specifically designed for industrial control systems, prioritize operational continuity and safety, focus on the most impactful security measures based on real attack analysis, and provide practical guidance for resource-constrained industrial environments.
Consider operational impact and safety requirements, resource allocation and staff training needs, integration with existing security programs, compliance with industry regulations, vendor selection for specialized ICS security tools, and ongoing maintenance and improvement of implemented controls.
Complete implementation typically takes 12-18 months depending on organizational size and existing maturity. Controls #1 and #3 (incident response and monitoring) show benefits within 90 days. Comprehensive defensible architecture and vulnerability management require longer-term commitment and operational coordination.
Challenges include operations team resistance to system disruptions, lack of OT security expertise among IT staff, difficulty obtaining accurate legacy asset inventories, budget constraints for specialized tools, and coordinating implementations with maintenance windows. Success requires executive sponsorship and cross-functional collaboration.
Success metrics include reduced incident response time for OT events, improved visibility into network activity and asset inventory accuracy, decreased unauthorized access attempts, enhanced vulnerability identification and remediation coordination. Establish baselines before implementation and track quarterly improvements through assessments.
SANS controls focus exclusively on highest-impact OT measures versus broad IT frameworks. While NIST provides comprehensive IT guidance, SANS prioritizes industrial-specific defenses. ISO 27001 emphasizes documentation; SANS emphasizes practical implementation. This attack-informed approach maximizes ROI for resource-constrained industrial environments. SANS controls align with and exceed major frameworks: NERC CIP requirements for electric utilities, FDA 21 CFR Part 11 for pharmaceuticals, IEC 62443 security levels, and NIST Cybersecurity Framework subcategories. Implementation supports integrated compliance reporting across multiple regulatory requirements.
Organizations typically see 15-25% reduction in security incident response time, 40-60% improvement in OT asset visibility, 30-50% reduction in unplanned downtime from security issues within first year. Cost avoidance from prevented incidents often exceeds implementation investment within 18-24 months.
Yes, prioritize based on your risk profile and constraints. High-risk environments should start with monitoring (Control #3) for immediate visibility. Regulated industries often prioritize incident response (Control #1). However, defensible architecture (Control #2) provides foundation for other controls’ effectiveness.
