Securing personal data under GDPR is essential, and Elasticsearch, powered by X-Pack, offers robust security features to meet these requirements. The post outlines the importance of protecting 'Personal Data' as defined by GDPR, which includes both Direct and Indirect Identifiers, and discusses pseudonymization as a method to enhance data security. It emphasizes the need for encryption in data transit and at rest, and highlights X-Pack's capabilities in user authentication through integration with systems like LDAP and Active Directory. The primary focus is on implementing role-based access controls (RBAC) and attribute-based access controls (ABAC) in Elasticsearch, demonstrating how these methods can limit data access based on user roles, document-level security, and field-level security, ensuring compliance with GDPR. Examples illustrate how RBAC can manage access to datasets by country and how ABAC can use user metadata to control data visibility, offering a scalable solution for both small and large organizations.