CVE-2021-41109

Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to version 4.10.4, for regular (non-LiveQuery) queries, the session token is removed from the response, but for LiveQuery payloads it is currently not. If a user has a LiveQuery subscription on the `Parse.User` class, all session tokens created during user sign-ups will be broadcast as part of the LiveQuery payload. A patch in version 4.10.4 removes session tokens from the LiveQuery payload. As a workaround, set `user.acl(new Parse.ACL())` in a beforeSave trigger to make the user private already on sign-up.

Source: CVE-2021-41109