Attacks and malware
What is Credential stuffing?
Automatically trying username and password pairs leaked from one site against other sites, betting that people reuse passwords.
Credential stuffing is the automated use of username and password pairs stolen from one service to log in to others. It works because many people reuse passwords.
Attackers use lists built from old breaches and stealer logs, plus tools that rotate IP addresses through proxies to avoid simple rate limits. Defences include multi-factor authentication, bot detection and checking passwords against known breach lists.