Creating and maintaining a data inventory is a crucial task for any organization that handles sensitive data and personal information. A comprehensive data inventory provides visibility into where data lives, how much of it there is, and the context around it. This visibility is essential for properly securing sensitive data and ensuring compliance with data privacy regulations.
Where did this come from?
This control comes from the CSA Cloud Controls Matrix v4.0.10, released on 2023-09-26. You can download the full matrix here. The Cloud Controls Matrix provides a comprehensive set of security controls specifically designed for cloud computing environments. It's an excellent resource for any organization using cloud services.
For more information on data classification and inventorying sensitive data, check out the AWS Data Classification Whitepaper. It provides an overview of data classification concepts and walks through how to implement a data classification scheme in AWS.
Who should care?
This control is especially relevant for:
- Chief Privacy Officers tasked with overseeing the organization's data privacy program
- Information Security Managers responsible for protecting sensitive data
- Compliance Officers who need to demonstrate adherence to data privacy regulations
- Data Stewards who manage and govern specific datasets
What is the risk?
Without a data inventory, an organization lacks visibility into what sensitive data it has and where that data resides. This opens the door to several risks:
- Sensitive data could be inadvertently exposed in a data breach if it's not properly identified and secured
- The organization may be out of compliance with data privacy regulations like GDPR or CCPA that require knowing what personal data is collected and where it's stored
- Sensitive data may be kept longer than necessary, increasing the impact of a potential breach
A thorough data inventory helps mitigate these risks by providing the necessary visibility to properly secure sensitive data throughout its lifecycle.
What's the care factor?
For organizations that handle sensitive data, especially personal information, maintaining a data inventory should be a top priority. The consequences of a sensitive data breach can be severe – reputational damage, regulatory fines, lawsuits, etc. Plus, many data privacy regulations now require organizations to maintain records of processing activities (ROPAs) which include data inventories.
However, for organizations with very limited sensitive data, the risk may be lower and a comprehensive data inventory may be overkill. The key is to match the level of effort to the level of risk based on the types and quantities of sensitive data in play.
When is it relevant?
Data inventorying makes sense whenever an organization collects, stores, or processes sensitive data, especially at scale. It's particularly important for:
- Organizations subject to data privacy regulations like GDPR, CCPA, HIPAA, etc.
- Cloud environments where data can be spread across many services and storage locations
- Big data applications with large volumes of data that may contain sensitive elements
On the flip side, a full-fledged data inventory may not be necessary for a small business with a single database containing limited sensitive data. In this case, the sensitive data is already well-known and additional inventorying may not provide much value.
What are the trade offs?
Maintaining an accurate, up-to-date data inventory requires time and effort. Some potential costs include:
- The man-hours needed to initially populate the inventory and keep it current over time as data changes
- Potential productivity impacts of data discovery tools scanning databases, file shares, cloud storage, etc.
- Opportunity cost of personnel working on inventorying versus other security/privacy initiatives
- Possible software costs for data discovery and inventorying tools
However, these costs need to be weighed against the risk reduction and compliance benefits a data inventory provides. For many organizations, a data inventory is well worth the effort.
How to make it happen?
Here's a step-by-step overview of implementing a data inventory:
- Define the scope of the inventory - what data types and storage locations will be included?
- Assign roles and responsibilities for the inventorying process - who will conduct discovery, who will maintain the inventory, etc?
- Select data discovery tools. This could include open source tools like OpenDLP or commercial solutions.
- Run data discovery scans on databases, file shares, cloud storage, etc. Many discovery tools can integrate directly with cloud APIs for scanning.
- Review discovery results and populate the inventory with relevant metadata - data type, sensitivity, owner, location, retention requirements, etc.
- Implement a process to keep the inventory current - rerunning discovery scans, collecting change logs, manual reviews, etc.
- Integrate the inventory with other security and privacy processes - DLP, encryption, retention, access control, etc.
What are some gotchas?
A few things to watch out for when implementing a data inventory:
- Discovery scans can be resource intensive, so plan for potential performance impacts
- Not all sensitive data will be found via automated discovery, manual review is still needed
- Keeping the inventory current is just as important as the initial population; outdated inventories provide a false sense of security
- Access to the inventory itself should be tightly controlled as it can act as a "treasure map" to sensitive data
Also be aware of the permissions needed to perform discovery scans. For example, to use AWS Macie for data discovery, you'll need permissions like macie2:PutClassificationExportConfiguration and s3:GetObject. See the Macie docs for full details.
What are the alternatives?
While a data inventory is considered a best practice, some alternatives for smaller-scale sensitive data management include:
- Tight access controls and encryption for the limited locations where sensitive data is stored
- Detailed documentation of sensitive data flows and locations in lieu of an actual inventory
- Vendor assessments and questionnaires to understand where third-parties store your sensitive data
