Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to 9.6.0-alpha.24 and 8.6.47, remote clients can crash the Parse Server process by calling a cloud function endpoint with a crafted function name that traverses the JavaScript prototype chain of a registered cloud function handler, causing a stack overflow. The fix in versions 9.6.0-alpha.24 and 8.6.47 restricts property lookups during cloud function name resolution to own properties only, preventing prototype chain traversal from stored function handlers. There is no known workaround.
The product receives input from an upstream component that specifies attributes that are to be initialized or updated in an object, but it does not properly control modifications of attributes of the object prototype.