n the world of computer networking, cloud computing makes a technical shift of computing services being provided locally to being provided remotely by third-party service providers. The data which was previously retained by the control of users now it's under the control of service providers. Cloud computing conveys numerous economic and practical assistances along with severe security alarms that might impend commercial endurance and business status. The cloud computing definition is still not clear in a huge portion, as of the extent of security threats and the large expanse of virtual information being distributed over the unsecured area. This manuscript aims to assess in what way security risk issues are affecting the surviving and eventual cloud platform. This survey examines the published resources and studies, examines available concerns laterally with existing countermeasures to assess the complete assertion level of security of the cloud. The primary goal of the survey is to analyse the security risks and the existing security algorithm's performance in terms of different security parameters. This study includes the basics of cloud computing by adding its characteristics, models, and their categories. The analysis also embraced the existing security concerns faced by researchers and their imposed methodologies.