1-800-427-9248 is a legitimate number for the Capital One fraud services. Another legit number is 1-800-215-1921
. I got a message to verify a recent purchase, and the message said to call back at "800-427-9248 or the number on the back of your credit card." I was cautious and called the main bank number, and was eventually transferred to the Fraud Unit. They had placed the call and they were indeed verifying a purchase.