I just came across an interesting practice question in the ISC2 study app. It laid out a scenario where the pen testing services had a scope given to them but didn't have any knowledge of the environment beyond the scope. The answer was that it was a "grey box test" I thought it was black.

If a scope counts as some knowledge of the environment, wouldn't that mean that a black box test would be impossible? Since a well-defined scope is a mandatory part of a pentest engagement?