DevSpace is a client-only developer tool for cloud-native development with Kubernetes. Prior to 6.3.21, DevSpace's UI server WebSocket accepts connections from all origins by default, and therefore several endpoints are exposed via this WebSocket. When a developer runs the DevSpace UI and at the same time uses a browser to access the internet, a malicious website they visit can use their browser to establish a cross-origin WebSocket connection to ws://127.0.0.1:8090. This vulnerability is fixed in 6.3.21.