I got a call from the above number informing about lowering all my master cards irrespective of the bank's rate. He first asked me for my master card's expiry. I said it and he confirmed that yes it is matching with his records. And then asked for 3 digits of back of my card. I gave it without thinking. He said that was matching. Then he asked me for the 16 digit card number starting with 5. Yes my master card number starts from 5. Then I asked him don't you have my full card number? Can you tell me what is my email ID from you records. Can you send mail to me with the lowering interest rates offer?
He then disconnected the call.

Please be cautious while some unknown call asks for your credit card information.