Credential stuffing occurs when a criminal tests large numbers of compromised credentials (i.e., usernames and passwords breached from another site) against your login application.
On average, one million usernames and passwords are reported spilled or stolen every day. Attackers acquire credentials in many ways, from discovering misconfigured databases to infecting users’ devices with malware.
Attackers route their login requests through proxy servers to avoid IP blacklists and other forms of detection. Criminals can purchase access to proxy services from bot herders on dark web forums for $2-$8 per hour.
Finally, attackers use bots, or computer programs, to automatically test the list of breached credentials. Attackers often purchase toolkits on the dark web, such as CAPTCHA solvers or anti-fingerprinting scripts, to help counteract existing defenses.
