ISO 27001:2022 Annex A Control 5.33

Implementing Annex A Control 5.33 requires a structured and strategic approach. Here are the main aspects your organization should address:

1. Establishing Storage and Handling Guidelines

Your organization should define and enforce policies that dictate how records should be stored, handled, and disposed of. This includes:

• Storage Conditions:
  Physical records should be stored in secure locations with restricted access.
  Digital records should be encrypted and backed up regularly to prevent data loss.
• Handling and Chain of Custody:
  Employees handling records should follow standardized procedures to prevent loss or manipulation.
  The movement of records should be tracked and logged for audit purposes.
• Disposal Procedures:
  Records must be disposed of securely to prevent unauthorized recovery.
  Shredding, digital wiping, and secure disposal services should be used for physical and electronic records.

2. Implementing a Record Retention Schedule

A retention schedule defines how long different types of records should be kept before disposal. Your organization should:

• Categorize records based on type:
  Financial records (e.g., invoices, tax filings)
  Legal records (e.g., contracts, compliance documents)
  Human resource records (e.g., employee files, payroll)
  Operational records (e.g., audit logs, incident reports)
• Determine retention periods
  Compliance with local and international legal and regulatory requirements is crucial.
  Industry-specific regulations, such as GDPR, HIPAA, SOX, dictate retention requirements for personal and financial data.
• Automate record expiration and disposal:
  Digital record management systems should provide alerts and automated actions for expired records.

3. Applying Access Controls and Permissions

To prevent unauthorized access to records:

• Role-Based Access Control (RBAC): Ensure employees can only access records relevant to their roles.
• Least Privilege Principle: Grant access only when necessary and revoke it when no longer required.
• Multi-Factor Authentication (MFA): Implement MFA for users accessing sensitive digital records.
• Audit Logs: Maintain logs of who accessed or modified records to detect potential security breaches.

4. Classification and Labeling of Records

To ensure appropriate protection:

• Label records based on confidentiality levels:
  Public
  Internal
  Confidential
  Highly Confidential
• Apply security measures accordingly:
  Encrypt highly sensitive records.
  Implement stricter access controls for confidential data.

5. Data Backup and Redundancy

To prevent data loss:

• Maintain offsite and cloud backups of important records.
• Use version control to track modifications and revert to previous versions if needed.
• Test backup restoration processes regularly to ensure reliability.

6. Ensuring Format Readability and Longevity

As technology evolves, outdated file formats may become unreadable. Your organization should:

• Standardize formats to ensure long-term readability (e.g., PDFs for documents, CSV for data sets).
• Monitor format obsolescence and migrate records to updated formats when necessary.

7. Secure Cryptographic Key Management

If records are encrypted, cryptographic keys must be retained for the entire retention period. Loss of decryption keys can render records inaccessible.

8. Secure Destruction of Expired Records

Records no longer required should be securely destroyed to prevent unauthorized recovery. Best practices include:

• For physical records: Use shredders or incineration.
• For digital records: Implement secure deletion techniques (e.g., data wiping, degaussing).