Blockchain technology has already gained significant importance in various fields involving medium to large scale applications. It has also gained research importance, in recent years, in order to make it application-friendly in terms of factors like security and de-centralization. Further research is also consistently going on towards Blockchain adoption, absorption, and business values. Out of these factors, security plays a significant part, so it is essential to understand the different threats affecting the Blockchain based applications to be considered while developing them. The proposed survey discussed here is based on various security risks revolving around Blockchain-based applications with the support of current state-of-the art research being carried out in different fields, such as IOT, Metaverse, Cloud based applications, and other relevant fields, it is believed that the proposed survey would greatly support the Blockchain application users and developers for the proper application of the technology.