Azure Storage Docs

Comprehensive documentation for Azure services

Access Control for Azure Storage Tables

This document explains how to secure your Azure Storage tables by implementing robust access control mechanisms.

Understanding Azure Storage Table Access Control

Azure Storage Tables offer several ways to control who can access your data and what operations they can perform. The primary methods include:

  • Shared Access Signatures (SAS): Delegated access with granular permissions for a limited time.
  • Access Control Lists (ACLs): Managing permissions at the container or table level for specific users or groups.
  • Azure Active Directory (Azure AD) integration: Leveraging Azure AD identities for authentication and authorization.

Shared Access Signatures (SAS)

SAS tokens provide a secure way to grant limited access to table resources without exposing your account keys. You can generate SAS tokens with specific permissions (e.g., Read, Write, Query, Update, Delete), an expiry time, and an IP address range.

Types of SAS:

  • Service SAS: Generated from an account storage credential, grants access to a specific storage service (e.g., Tables).
  • Account SAS: Grants access to one or more storage services, and can include permissions at the service, container, and object levels.

Important: Always generate SAS tokens with the minimum necessary permissions and shortest possible validity period to enhance security.

Generating a SAS Token (Example using Azure CLI):


az storage table generate-sas --account-name mystorageaccount --account-key YOUR_ACCOUNT_KEY --name mytable --permissions rqu --expiry 2024-12-31T12:00:00Z

Access Control Lists (ACLs)

ACLs allow you to define access policies for individual tables. This is a more static form of access control compared to SAS.

  • Permissions: Define allowed operations (e.g., Read, Insert, Update, Delete, Query).
  • Principals: Specify users or service principals that are granted these permissions.

Tip: Use Azure AD for managing user identities when ACLs become complex to maintain.

Azure Active Directory (Azure AD) Integration

For robust enterprise-level security, integrate Azure Storage Tables with Azure AD. This allows you to use familiar Azure AD identities (users, groups, service principals) to authenticate and authorize access.

  • Role-Based Access Control (RBAC): Assign Azure roles to Azure AD identities to grant permissions on storage accounts or specific resources. Common roles include "Storage Table Data Reader" and "Storage Table Data Contributor".
  • Managed Identities: Enable your Azure applications to authenticate to Azure Storage without needing to manage credentials.

Steps for Azure AD Integration:

  1. Enable Azure AD authentication on your storage account.
  2. Assign appropriate RBAC roles to your Azure AD users, groups, or service principals.
  3. When accessing the table, use Azure AD credentials for authentication.

Best Practices for Table Access Control

  • Principle of Least Privilege: Grant only the permissions necessary for users or applications to perform their tasks.
  • Regularly Review Permissions: Periodically audit access policies and revoke unnecessary permissions.
  • Use Azure AD for Centralized Management: Leverage Azure AD for managing identities and access policies across your Azure resources.
  • Monitor Access: Utilize Azure Monitor and Azure Storage analytics to track access patterns and detect suspicious activity.
  • Securely Store Credentials: Avoid hardcoding account keys or SAS tokens directly in application code. Use Azure Key Vault.

By implementing these access control strategies, you can significantly enhance the security posture of your Azure Storage tables.