Sensitive data identification is a vital strategy in any distributed system. However, in the case of non-appropriate utilization of the system, sensitive data security can be at risk. Therefore, sensitive data identification and its security validation are mandatory. The paper primarily focuses on novel sensitive data recognition methodologies. Further, the sensitivity score of the attributes distinguishes non-sensitive attributes, and domain expert plays an important role in this process. The designing of the security assurance Algo and their corresponding decision tables make the system more robust and reliable. The result section is validated with the help of graphical representation, which clearly makes the authenticity of the research work. In summary, the authors may say that the sensitive data identification and security assurance of the proposed system is automated and work optimally in a cloud-based system.