ISO 27001 Control 5.19: Information Security in Supplier Relationships

What this means

Control 5.19 mandates that organizations establish and maintain documented processes to govern information security risks introduced through suppliers and service providers. This includes assessing supplier security capabilities before engagement, defining security requirements in contracts, monitoring ongoing compliance, and maintaining procedures for responding to supplier security incidents. The control acknowledges that reliance on external vendors creates dependencies that must be actively managed to protect your organization's information assets.

How to comply

1. 1.Identify all suppliers and service providers who have access to your information systems or data
2. 2.Assess the information security risks associated with each supplier's products, services, and access levels
3. 3.Define information security requirements in supplier contracts, including data protection, incident reporting, and audit rights
4. 4.Evaluate supplier security controls before engagement (certifications, assessments, security documentation)
5. 5.Document supplier risk assessments and approval decisions in a centralized register
6. 6.Establish monitoring procedures for ongoing supplier compliance and security posture
7. 7.Create a process for reviewing and renewing supplier agreements at defined intervals
8. 8.Define escalation procedures for supplier security incidents or control breaches
9. 9.Train relevant staff on supplier risk management and secure third-party engagement practices

Evidence auditors look for

• Documented supplier risk assessment methodology and scoring criteria
• Completed risk assessments for all active suppliers with documented decisions
• Supplier security requirements documented in contracts or agreements
• Evidence of supplier security evaluations (audit reports, certifications, questionnaires)
• Supplier management register tracking risk levels, renewal dates, and contact information
• Supplier monitoring reports showing ongoing compliance checks
• Incident logs documenting supplier-related security events and remediation actions
• Third-party agreement templates with information security clauses
• Training records for staff involved in supplier management and procurement

Frequently asked questions

GRCWatch automates supplier risk assessments, tracks security questionnaire responses, and maintains your supplier register with automated renewal reminders—eliminating manual spreadsheets and ensuring no supplier gaps slip through your compliance program.

See how GRCWatch handles this control automatically

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