This is a very serious problem right now. Scammers breach your email security, and send you a very real looking email from what appears to be your title company, real estate agent or bank. The email attempts to make you believe there is a need for a wire fund transfer and provides erroneous transfer info which sends the money to the thief. This transfer usually occurs at a time when a wire transfer would normally be expected.
Victims not only lose tens or hundreds of thousands of dollars, they generally lose the opportunity to complete the sale of their home due to lack of funds.
Check out this great video provided by the National Association of Realtors.
As stated in the video, always call the person requesting the transfer from a secure phone number that you already have and confirm that a transfer is needed, and that the transfer information you have been provided is correct.