It works if you enter the code manually, yes but then USSD codes are designed to work that way (same as *#06#). This is not a bug. The bug that was fixed was the auto execution of USSD codes when "clicked" from a webpage link, SMS link or NFC/QR Code.
Are you saying you browsed to this page on your Galaxy S3, clicked the tel: link and it reset your phone without further user interaction?
Funny, doesn't do it on mine and all websites are reporting this to be the case as well...
Edit: When I click it, the dialler comes up with the code in it for a second, before disappearing thus not allowing me to do anything with it