With a little truth, the social engineering becomes harder to spot
Information is an important key to a credible fraud attempt, and fraudsters make sure to gather as much information as they can before they act. A completely fabricated invoice can easily be dismissed, but if they instead hijack a real invoice and change the account number it should be paid to, it's much harder to detect this.
"Making small adjustments to genuine information instead of fabricating completely new content is an increasingly common approach. This could involve changing a recipient account, a salary account or some other payment detail."
The fraudsters can stage their fraud attempt from genuine email addresses that they have breached, or they create their own addresses that are very similar to the addresses they want to pretend to send from.
Verify and call back
A BEC fraud can affect the company from within, but it can also be a supplier or business partner. It could be an invoice from a subcontractor that has been manipulated, and even if you haven't been targeted yourself, you are affected by this.
"An important step to protect yourself is to verify and call back. If changes are to be made to recipient accounts or payment details, don't do this based solely on a written request. Pick up the phone and call back. Verify that the recipient really has a new account number before you follow instructions."