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📖 What is Data Custodian?

A Data Custodian is responsible for the secure storage, maintenance, and operational protection of data as directed by the Data Owner. This includes implementing access controls, performing backups, ensuring data integrity, and responding to security incidents related to the data under their care.

🥋 Sensei Says:

"The Data Custodian is typically an IT or security role. The exam will test your understanding of their technical responsibilities in enforcing the Data Owner’s policies. Remember, they *implement* security controls; they do not *define* them."

📚 Certification: Certified Information Security Manager (CISM)

🔑 What are the Key Concepts of Data Custodian?

▸ Data Custodians implement access controls (e.g., permissions, encryption) defined by the Data Owner to restrict data access to authorized users.
▸ They are responsible for the technical aspects of data protection, including backups, disaster recovery, and data integrity verification.
▸ Incident response related to data breaches or security events falls under the Data Custodian’s purview, following established procedures.
▸ Custodians must adhere to data retention policies and ensure data is securely disposed of when no longer needed, complying with regulations.
▸ Understanding the separation of duties is crucial: Custodians *do* not determine data sensitivity or classification – that’s the Data Owner’s role.

🎯 How does Data Custodian appear on the CISM Exam?

You may be asked to identify which role is responsible for configuring and maintaining data encryption at rest and in transit, given a scenario describing data storage requirements.

A scenario might describe a data breach; expect questions about the Data Custodian’s immediate actions, such as isolating affected systems and initiating incident response protocols.

Expect questions about the Data Custodian’s role in ensuring compliance with data privacy regulations (e.g., GDPR, CCPA) through technical controls and data handling procedures.

❓ Frequently Asked Questions

What’s the difference between a Data Custodian and a Data Steward?

Data Stewards focus on data quality, definition, and business rules, while Custodians handle the technical security and operational aspects of data storage and protection. They work together, but have distinct responsibilities.

If a Data Owner changes a data classification, what does the Data Custodian need to do?

The Custodian must implement the changes to access controls, encryption settings, and other security measures to align with the new classification level. This requires close communication with the Data Owner.

Can a Data Custodian delegate their responsibilities?

While tasks can be delegated, the ultimate responsibility for data security and protection remains with the Data Custodian. Delegation must be documented and appropriate oversight maintained.

Related Terms from Certified Information Security Manager

Data Classification Single Point of Failure Incident Identification Control Objective Availability Compliance

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