Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. If the Parse Server option allowCustomObjectId: true is set, an attacker that is allowed to create a new user can set a custom object ID for that new user that exploits the vulnerability and acquires privileges of a specific role. This vulnerability is fixed in 6.5.9 and 7.3.0.

Parse Server's custom object ID allows to acquire role privileges