Probably easy to fake with a little effort, but that's why you should have EBay, Paypal or whatever options to return the product or get your money back as well as check the EBay score of the seller.
Other:
It's still a great CPU for basic office or even light gaming. I have the i7-860 which is basically identical in my sister's PC (hand-me-down) with W10 on it working great.
May eventually see a virus though due to Spectre/Meltdown that Windows and/or anti-virus can't stop. I would consider using Acronis True Image or similar to automate an OS partition backup if you have important info.