The 'Azure Storage Blob Bulk Extraction' rule is designed to detect potential high-volume blob extractions, specifically targeting situations where there are more than 50 'GetBlob' operations within a 15-minute timeframe from an Azure Storage account. This alert scenario primarily arises from threats such as the Storm-0501 actor, known for rapidly extracting data using compromised credentials prior to initiating ransomware attacks. The rule emulates the functionality of a similar alert in Microsoft Defender for Cloud, which notifies users about unusual data extraction activities within their storage accounts. The detection mechanism entails monitoring Azure Monitor Activity logs to capture relevant blob operations and simplifies the examination of traffic anomalies by leveraging historical access patterns and generated SAS tokens. The associated tests include checks for successful blob extraction, case insensitive matches for operation names, handling of different operation types (e.g., put versus get), and identification of failed operations due to authorization failures. These analyses help provide a comprehensive understanding of the activity's legitimacy and potential dangers, guiding a swift response by security teams.