While answering an HR interview, sometimes this question can be asked to you. These days the interviewers are quite aware that candidates come prepared for the most commonly asked interview questions which can be easily found over internet. So they try to surprise you with such questions which you may not even hear of.
In such situation, try to appear calm. This is your chance to express your best old performance appraisals given by your last boss by your own mouth. This is a great way to brag about you through someone else's words.
An example can be, "My boss has told me that I am the best marketing manager he has ever had. He knows he can rely on me, and he likes my communication skills, intelligence, sense of humor and presence of mind."
But be prepared because you might be asked a return question based on your response. For instance an interviewer can ask you in return to the above answer, "how you think your sense of humor helps you in your everyday work?" or "why you think you have good presence of mind?" In such tricky questions, you should be able to demonstrate your quality with an example.
Many companies conduct background checks for the candidates before they decide to hire them or even after once they hire them. In such checks, your old company is visited preferably your old manager or HR executive of that organization. Make sure their views and your answers do not differ completely.
How can you do that?
Do not preach about qualities you don't have! Chances are you will end up in a difficult situation. Also do not talk about the qualities that were not recognized by previous seniors. If they have not recognized then they will never talk about that.
I'll advise you to stick to what your old managers have said about you in real or on paper to the maximum extend.