Cloud computing is the promising invention that is used to change the IT business. Cloud computing has various advantages such as adaptability, resource sharing, fast execution, and unlimited storage space. The virtual machines (VMs) are implemented for parallel processing of different types of data at same time. VMs face various security threats as an institutional component of cloud computing levels. Nevertheless, the existing systems should concentrate on resolving security threats on VMs. Presently, VM lifecycle security assurance framework is based on the believed registration of clients for authentication. Right now, the collaborative concepts for cloud computing virtualization and various social insurance records have been audited for security issues of VMs. In this paper, various reviews have presented on VM security and privacy issues related to virtualization.