In modern enterprise environments, cloud computing is the dominant force driving digital transformation. The need for robust cloud security mechanisms has become paramount. Cloud security comprises technologies that are designed to safeguard cloud-based systems, applications, and data from threats. This systematic review aims to explore the adoption of cloud security architectures, challenges with cloud transformation, and emerging trends in cloud security, with a particular focus on Secure Access Service Edge (SASE), a rapidly evolving security framework. Traditional security approaches are not appropriate for dynamic, multi-tenant cloud environments. To address these complexities, a unified cloud-native platform such as SASE has been introduced to merge network and security services. However, despite the technological advancements, organizations are facing challenges in adopting and integrating security mechanisms with the existing infrastructure. As cloud adoption is accelerating at an alarming rate, the adoption of SASE is a significant step forward in the cloud security space. The key findings revealed that the post-pandemic surge is driving the reengineering of cloud security strategies, but organizations are facing implementation and migration challenges due to the evolving security risks and requirements of aligning with industry best practices. Although SASE is a comprehensive technology comprising advanced security solutions, the integration is complex in nature, and the practical impact on organizations has not been fully explored.