Investigate and respond to alerts generated from Data Loss Prevention policies

Data Loss Prevention (DLP) policies are a crucial component in an organization’s security infrastructure, as they help to detect and prevent sensitive information from leaving the corporate network unintentionally or maliciously. The SC-200 Microsoft Security Operations Analyst exam assesses a candidate’s ability to configure Microsoft security technologies, respond to incidents, and enforce data governance, where DLP plays a key role.

When a DLP policy is triggered, it generates an alert indicating that there is a potential data leak or unauthorized data transfer in progress. Security operations analysts must investigate these alerts promptly to understand the context and take appropriate action.

Investigation of DLP Alerts

Upon receiving a DLP alert, analysts should take the following steps:

1. Alert Identification: Understand which DLP policy was triggered and what type of sensitive information is involved.
2. Context Gathering: Review the alert details to determine the severity and scope of the potential data breach. Analysts should look at who is involved, what content was transferred, and how it was transmitted.
3. User Activity Assessment: Evaluate the user’s history and behavior pattern to determine if the incident is consistent with typical job function activity or if it appears to be anomalous or malicious.
4. Content Inspection: Inspect the content that triggered the DLP alert to validate if it indeed contains sensitive information.
5. Incident Timeline Construction: Build a timeline of events leading up to and following the alert trigger to visualize the sequence of actions and understand the potential data flow.
6. Policy Evaluation: Review the DLP policy itself to ensure it is configured correctly and is not generating false positives.

Response to DLP Alerts

After the investigation, the analyst must respond appropriately to mitigate risks and enforce company policies on data security.

1. Incident Severity Assessment: Classify the severity of the incident based on the data involved and the potential impact if it were to be disclosed.
2. Notification Protocol: Follow the organization’s incident response plan, which may involve notifying the user, management, legal, and compliance teams.
3. Rectification and Remediation: Take corrective actions which may include revoking shared links, blocking user actions, or initiating legal holds on emails or documents.
4. User Education and Awareness: If the alert resulted from user error, implement additional training to improve awareness of data handling policies.
5. Policy Adjustments: If false positives are an issue, or if genuine leaks are not being detected, modify the DLP policy rules to improve accuracy.
6. Documentation and Reporting: Record the details of the incident and the response in a security information and event management (SIEM) system for future reference and compliance auditing.

Example Scenario

A DLP alert is generated indicating an employee tried to send a document containing credit card information to an external email address. On investigation, the analyst could observe:

• The user’s job does not typically involve the external sharing of such data.
• The document was classified as ‘confidential’ with credit card numbers clearly marked.
• An attempt to share the document was made through a personal email account.

The response might include immediately blocking the sending of the document, reaching out to the user to verify their intentions, and adjusting outbound email filtering to deliver more stringent checks before allowing the sending of sensitive information.

Comparison of DLP Response Actions

Managing and responding to DLP alerts is a dynamic and critical task for security operations analysts. By thoroughly investigating and smartly responding to DLP policy alerts, analysts contribute to protecting against data breaches, maintaining regulatory compliance, and upholding the integrity of sensitive company information.