Occurs when a fraudster uses a merchant’s website to “test” stolen credit card information to determine if the card is valid. Fraudsters can purchase lists of credit card numbers online on the dark web at a low cost but often do not know if the cards they are purchasing are active. To test these cards, fraudsters often use automated bots and scripts to run many of these numbers through a merchant’s checkout page. If a transaction is approved, the fraudster knows that the card is valid and can make fraudulent high-value purchases elsewhere.
Read Kount’s blog on Card Testing and how they can lead to big losses.