Unusual access to Microsoft 365 storage services

Synopsis

Field	Value
Activation Period	14 Days
Training Period	30 Days
Test Period	N/A (single event)
Deduplication Period	5 Days
Required Data	Requires one of the following data sources: Azure Audit Log OR Microsoft Graph Logs
Detection Modules	Cloud
Detector Tags	Microsoft Graph Activity Logs
ATT&CK Tactic	Discovery (TA0007)
ATT&CK Technique	Cloud Service Discovery (T1526)
Severity	Informational

Description

Unusual access was detected to a Microsoft 365 storage service.

Attacker's Goals

Extract sensitive information stored in Microsoft 365 storage services.

Investigative actions

• Determine which items were accessed.
• Identify whether they contained any sensitive information.
• Check for signs of a compromised identity, such as abnormal login activity or unusual behavior.
• Verify if the identity is authorized to access these drives.
• Monitor the identity for any further suspicious actions.

Variations

Unusual access to Microsoft 365 storage services from an uncommon IP

Synopsis

Field	Value
ATT&CK Tactic	Discovery (TA0007)
ATT&CK Technique	Cloud Service Discovery (T1526)
Severity	Low

Description

Unusual access was detected to a Microsoft 365 storage service.

Attacker's Goals

Extract sensitive information stored in Microsoft 365 storage services.

Investigative actions

• Determine which items were accessed.
• Identify whether they contained any sensitive information.
• Check for signs of a compromised identity, such as abnormal login activity or unusual behavior.
• Verify if the identity is authorized to access these drives.
• Monitor the identity for any further suspicious actions.