The risks are as follows:

Someone could intercept your data and read the information you’ve submitted, which includes your Social Security Number and your tax information. How likely is this to happen? Not very likely. As your data travels through the Internet it takes a random path through the thousands of lines and computers that form the Internet. A data thief would essentially have to guess what path your data was taking and wait for it to pass through to intercept it. After the data was intercepted it would also have to be decrypted or unscrambled to read it.