Currently, we do not investigate this. For widgets this is not a big problem, since the usually security rules from your app apply, however, for modules this is indeed an issue. We check the code roughly, and investigate whether it complies to the functionality described in the documentation, but we do not apply an in depth security check. For now the usage of any AppStore item is at own risk.
I would recommend to think about these issues because it will play a role in strategic decisions of larger companies.