It's not a "certified" check, just a "Cashier's Check".

But even so, you can easily fake Certified Checks. I even got a bad USPS Money order one time. There are check writing programs available, along with stationary suppliers who sell check blanks, and places to buy magnetic ink that the checks are printed with. For a few dollars $20 or $200 or whatever, you can print up perfectly legitimate checks for your small business, or for your scam. They will go through the banking system just fine until the bank they are drawn on refuses payment as there is no such account (for a faked check).

30 years ago a certified check would almost certainly be good. Now I would not deposit anything that I was not 100% certain of the source, as I don't want to pay the returned check fee. Not to mention that on any deposit I don't plan a spending a dime of it until a couple of days after my bank says they have good funds!

[P.S. that magnetic ink is a problem for the bankers and the government... You can find the pattern of magnetic ink spots used on currency that the bill acceptors read, print up your own $20's and feed them into the machines. Problem here is the Secret Service actually takes this very seriously, unlike printing up fake checks.]