It is a feature [0].
Microsoft office products allow for "macros" which are Visual Basic code embedded within a document or a worksheet that can be used by developers to add extra functionalities to their MS files (e.g. validate all data in a work sheet after a user clicks a specific button in the worksheet).
Just like any programming language, it could be used maliciously, and there is no easy way to distinguish which macro-enabled file is safe and which isn't (without going through the code yourself prior to enabling the functionality)
Just like any programming language, it could be used maliciously, and there is no easy way to distinguish which macro-enabled file is safe and which isn't (without going through the code yourself prior to enabling the functionality)
[0] https://support.office.com/en-us/article/Enable-or-disable-m...