Vendor Risk Assessment for OT Integrators: What to Evaluate

Your OT integrators are entrusted with your most critical systems. They design your control architectures, maintain your PLCs, and often have credentials to access your systems remotely. Yet many industrial organizations conduct minimal due diligence on integrators' security practices before engaging them. An integrator without security competency is a vulnerability. One that's been compromised is a backdoor into your systems. Rigorous vendor risk assessment is essential.

Vendor risk assessment for integrators goes deeper than checking financial stability or references. You need to understand their security culture, their development practices, their incident response capability, and their track record managing vulnerabilities. This requires a structured assessment process and ongoing monitoring, not a one-time evaluation.

Vendor Assessment Framework

Start with a questionnaire covering security governance, development practices, vulnerability management, and incident response. Ask whether they have a security policy, security training, code review practices, and vulnerability disclosure procedures. Ask for evidence—audits, certifications, assessments. Ask about their incident response experience. Have they discovered vulnerabilities in customer systems and how did they handle notification and remediation? These questions reveal whether security is built into their business or an afterthought.

Request references from current customers and ask specifically about security practices. Ask whether vulnerabilities have been discovered in systems the integrator deployed, how the integrator handled notification, and whether patches were provided promptly. Use this feedback in your risk assessment. An integrator with a track record of slow vulnerability remediation is a risk.

Key Assessment Criteria

• Security governance and policy: Does the vendor have a documented security policy, assigned security roles, and evidence of security culture? Does leadership understand and support security investment?
• Secure development practices: Do they conduct threat modeling, code review, security testing? Are they following frameworks like 62443? Do they document their practices?
• Vulnerability disclosure and response: Do they have a process for receiving vulnerability reports? What's their typical time to remediation and patch deployment? Are they transparent with customers about vulnerabilities?
• Supply chain security: If they use third-party components or subcontractors, how do they vet and manage security? Do they require vendors to meet security standards?
• Incident response and forensics: If they've been compromised or discovered security incidents in their own systems, how did they respond? Can they demonstrate incident response capability?

Ongoing Vendor Management

Initial assessment is important, but ongoing monitoring matters more. Require integrators to notify you promptly of vulnerabilities affecting systems they've deployed. Require them to provide patches or workarounds within defined timeframes. Conduct annual security reviews with vendors. For critical vendors, request periodic security audits or assessments. Maintain a vendor risk register that documents known risks and mitigation strategies.

Building integrator accountability takes effort, but it's essential. Your control systems are only as secure as the people designing and maintaining them. We help industrial organizations assess vendor security, build vendor management programs, and maintain ongoing oversight of critical integrators. Let's discuss vendor security assessment for your operation.