Snowflake: Securing Data at Rest and in Transit


This guide outlines Snowflake's encryption features for protecting data at rest and in transit, utilizing AES-256 and TLS protocols. It details both built-in and customer-managed key management options, with a focus on setting up Customer-Managed Keys for greater encryption control. Best practices, including key permission audits and monitoring, are provided to enhance Snowflake's data security measures. This concise overview helps organizations strengthen their encryption and key management strategies in Snowflake.

Snowflake provides robust security features to protect data at rest and in transit, employing comprehensive encryption mechanisms as a core aspect of its security architecture. Understanding and optimizing these features are crucial for maintaining data confidentiality and integrity.

Understanding Encryption in Snowflake

Data at Rest Encryption

  • Automatic Encryption: Snowflake automatically encrypts all data at rest using AES-256 strong encryption. This includes all data stored in tables, warehouses, and stages.
  • Transparent to Users: Encryption and decryption processes are entirely transparent, requiring no action from the user.

Data in Transit Encryption

  • TLS Encryption: All data in transit to and from Snowflake is secured using TLS (Transport Layer Security) protocols, ensuring that data is encrypted during transmission over the network.

Key Management in Snowflake

Built-in Key Management

  • Automated Key Rotation: Snowflake manages encryption keys, rotating them regularly without user intervention.
  • Hierarchical Key Model: Snowflake employs a hierarchical approach, with a master key encrypting key encryption keys (KEKs), which in turn encrypt data encryption keys (DEKs) used for actual data encryption.

Customer-Managed Keys (CMK)

  • Enterprise Feature: For organizations requiring additional control over encryption keys, Snowflake supports Customer-Managed Keys (CMK) through integration with cloud provider key management services (KMS).
  • Direct Control: Using CMKs, customers can manage the master key rotation and permissions, providing an extra layer of control and security.

Enhancing Default Encryption Settings

Activating Customer-Managed Keys (CMK)

  1. Choose a KMS Provider: Select a key management service provider, such as AWS KMS, Azure Key Vault, or Google Cloud KMS.
  2. Create a Master Key: Generate a master key in your chosen KMS. This key will be used by Snowflake to encrypt your KEKs.
  3. Configure Integration in Snowflake: Follow Snowflake’s documentation to configure the integration with your KMS, ensuring Snowflake can use your CMK for encryption operations.

Best Practices for Data Encryption

  • Regularly Review Key Permissions: Regularly audit permissions for your CMKs to ensure only authorized roles can access or rotate the keys.
  • Monitor Key Usage: Utilize your KMS’s monitoring features to track the usage of your CMKs, identifying any unauthorized attempts to access or use your keys.
  • Educate Teams on Encryption Practices: Ensure that your team understands the importance of encryption and the role of key management in securing data.

Snowflake’s default encryption mechanisms provide strong security for data at rest and in transit, ensuring that data is protected against unauthorized access. For organizations seeking additional control over encryption keys, Snowflake’s support for Customer-Managed Keys offers the ability to manage and rotate keys according to specific security policies. By understanding and leveraging Snowflake’s encryption features and following best practices for key management, organizations can achieve a high level of data security and compliance.