To file your taxes, you enter your Social Security Number, bank account details, home address, and income information. A cracked version of TurboTax can easily include a "keylogger" or "backdoor" that sends every keystroke and piece of data directly to a cybercriminal [2].
What did they do? Well, they offered a version of their software called TurboTax Free Edition. Unfortunately, they kinda violated, Cracked.com How TurboTax (Secretly) Makes Your Taxes A Nightmare turbotax new cracked