The original title to the question was : -
Are Decibels Inherently Ambiguous?
I personally think the title is fine but if the meddlers want to change things without checking to see if my answer may actually refer to the original title then so be it. Back to my original answer: -
It unambiguously applies to both.
If voltage increases by 3dB it is 1.4142 times bigger. If the power increases by 3dB it is 2 times bigger.
Absolutely no ambiguity there in any shape or form.