Credential stuffing is a type of cyberattack where criminals use stolen usernames and passwords from one data breach to try to break into other accounts where people use the exact same login details.
Credential stuffing uses stolen login credentials across multiple websites, using bots for mass log-in attempts.
How Credential Stuffing Works
A typical credential stuffing attack generally follows three steps
Obtaining leaked credentials from data breaches, phishing, or dark web purchases.
Automated testing where bots rapidly test these credentials on multiple sites, rotating IP addresses to avoid detection.
Account exploitation where successful logins allow criminals to steal data, make unauthorized purchases, send phishing messages, or resell credentials.
Detection and Prevention
Organizations can detect and respond to credential stuffing attacks as they happen by monitoring login patterns, identifying unusual behaviors, and using AI-driven tools. Multi-factor authentication adds an extra verification step, making it much harder for attackers to access accounts even if they have stolen credentials.
Additional defenses include rate limiting login attempts, implementing CAPTCHA challenges, using device fingerprinting, and deploying bot detection tools. Organizations should also monitor for unusual login activity such as logins from new locations or devices, and alert users to suspicious access attempts.