Improper Authorization in MongoDB Server Aggregation Framework View Definition Validation Leads to Unauthorized Collection Access

An authorization weakness in the aggregation framework of MongoDB Server may allow an authenticated user holding only basic database privileges to read the contents of collections in a database for which they have not been granted read access. The privilege evaluation performed while a view definition is validated does not cover a nested portion of the supplied pipeline, so the resulting view returns data the user is otherwise refused. This may result in unintended access to data, including stored authentication material.