This paper explores the enhancement of Information Security Management Systems (ISMS) through the adoption of Zero Trust architecture, focusing on its implementation in South Korea. The study examines the limitations of traditional ISMS models, particularly the Korean Information Security Management System, and posits that integrating Zero Trust principles can address these shortcomings. Utilizing a case-study approach, this paper provides an in-depth analysis of the Zero Trust model, with specific emphasis on Multi-Factor Authentication and Decentralized Identifiers. It presents real-world implementations and discusses policy frameworks that South Korea has adopted to transition towards Zero Trust. This research aims to contribute to both the theoretical and practical understanding of integrating Zero Trust architecture in ISMS protocols, offering insights into overcoming challenges and future directions.