Credential stuffing is a growing threat. It is not new, but for many companies it is treated as annoying background noise that can be absorbed by bandwidth, handled by access controls, and ignored. New figures suggest that this is a bad approach.
Credential stuffing typically uses bots to test many hundreds of thousands of stolen credential pairs against fresh targets. It doesn't afford a high return for the attacker, but it is a low cost, low risk attack that occasionally hits the jackpot. The attacker is relying on users' habit of reusing the same password across multiple accounts.
It isn't clear exactly where the credentials come from -- but there have been dozens of major breaches, hundreds of minor breaches, and an unknown number of unreported breaches over the last few years -- and we know that criminals aggregate stolen databases and sell them on. We are usually told that stolen passwords have been hashed; but since credential stuffing can only happen with plaintext...(continued)
