Cybersecurity

Microsoft Azure Storage logs play a critical role in digital forensics by providing vital evidence in security breach investigations. These logs are essential for detecting unauthorized access, tracing attacker activity, and protecting sensitive data. Azure Storage Accounts, known for their scalability and ability to host important business data, are frequently targeted by cyber attackers. Threat actors may exploit weak configurations, leaked credentials, or Shared Access Signatures (SAS tokens) to gain access, potentially copying, deleting, or exfiltrating sensitive files.

Enabling diagnostic logging is crucial as it allows organizations to capture and analyze traces of suspicious activities that might otherwise go unnoticed.

What Storage Logs Capture

Azure Storage logs track actions such as file uploads, downloads, and deletions across various services, including blobs, files, queues, and tables. The StorageBlobLogs table within Log Analytics is particularly valuable during incident investigations, capturing key details such as:

• OperationName: The action taken, such as uploading or deleting a file.
• AuthenticationType: The method of access, whether via SAS token, account key, or OAuth.
• CallerIpAddress: The source of the request, which helps identify unusual access locations.
• UserAgentHeader: The tools or browsers used to access a storage account.
• RequesterUpn: The account interacting with the system.

These data points help reconstruct a timeline of an attacker’s actions and determine if stolen secrets, such as SAS tokens, were used.

Detecting Security Incidents

Investigators can use logs to uncover various attack behaviors, including:

• Enumeration attempts: A sudden increase in failed requests may indicate unauthorized probing.
• SAS token or key misuse: Logs can show when sensitive operations are performed with atypical access methods.
• Role modification: Activity logs may reveal attempts to assign new roles or gain access to resources.
• Suspicious authentication types: Shifts in authentication methods may indicate lateral movement or token theft.

Azure Storage logs provide unmatched visibility into storage misuse, helping investigators contain ongoing attacks and identify configuration and access control gaps. By analyzing patterns in access methods, user behavior, and system responses, organizations can refine their defenses and reduce the risk of future data theft.

By leveraging these tools, organizations not only accelerate incident response but also enhance their resilience against future cyber intrusions.