npm parcel 2.0.0-alpha and before has an Origin Validation Error vulnerability. Malicious websites can send XMLHTTPRequests to the application's development server and read the response to steal source code when developers visit them.
https://github.com/parcel-bundler/parcel/issues/10216
https://github.com/parcel-bundler/parcel/discussions/10089
https://github.com/parcel-bundler/parcel/commit/4bc56e3242a85491c7edf589966e9b44c6330c49
https://gist.github.com/R4356th/41f468def606b2406e36f7193f5322b8