Since cloud computing offers its consumers flexible and pay-per-use services, it has become the favoured option for all IT organisations. However, because of its open and dispersed architecture, which leaves it exposed to hackers, security and privacy pose a significant obstacle to its development. Cloud intrusion detection systems, or IDSs, are the most widely utilised technique for this purpose. This document offers a summary of various cloud incursions. We next look at a couple of the most recent intrusion detection systems (IDS) that are cloud-based, and examine their type, location, detection time, method, data source, and potential threats. The study also outlines the limitations of each method so that it can be decided which one best meets the security requirements of the cloud computing environment. To address cloud security concerns, we emphasise the use of intrusion detection systems (IDS), which make use of a variety of detection methodologies.