Trick question. If you know about blind spots, they are no longer blind spots. Do not reveal any personal areas of concern here. Let them do their own discovery on your bad points. Do not hand it to them.
I would say everyone has blind spots and i would too. And that is why I believe in teamwork because when you are a team you can point out other people's blind spots and they will do the same for you.
Don't be too specific of your actual weakness..but instead try to bring out that you are very team oriented.
As a hiring manger, you do NOT want to be too generic with your response as it comes across as holding something back. It's assumed we all have blink spots, so I would not avoid the question. I recommend talking to it honestly and how addressing it will benefit yourself and the employer. An example answer could be "The bindspot that I recognize about myself is my tendency to focus on the immediate task and not take the initiative to understnad the bigger picture of the why it drives success of the business. I feel understanding the larger picture will further my ability to contribute to my job and is something I'm working to overcome."