A secondary market is any resale channel where goods are sold after the original retail purchase. In cyber security, the term matters because attackers often use these markets to move stolen or fraudulent items, including accounts, gift cards, hardware, and access credentials. Even when the item itself is not malicious, the resale layer can hide who originally owned it, how it was obtained, and whether the listing is legitimate.
Secondary markets create both attack opportunities and defensive signals. Criminals may use them to launder stolen goods, test demand for counterfeit products, or advertise compromised accounts and services. Defenders watch these spaces for brand abuse, unusual pricing, fake seller profiles, and listings that match known fraud patterns. For buyers, scarcity can increase risk: urgency makes it easier to miss warning signs, while weak verification can turn a normal purchase into a trust problem.