Credential Stuffing is an automated attack that uses stolen username/password pairs from previous data breaches to gain unauthorized access to other accounts.
Credential Stuffing
Credential Stuffing is an automated attack that uses stolen username/password pairs from previous data breaches to gain unauthorized access to other accounts.
Why It Matters
With billions of breached credentials available on the dark web, credential stuffing is one of the most common attack vectors. OWASP ranks it as a top API security risk, and Verizon's 2024 DBIR found that stolen credentials are involved in 44% of breaches.
How It Works
Attackers obtain credential dumps from previous breaches, then use automated tools to test these credentials against login endpoints across many services. Because people reuse passwords, a significant percentage of attempts succeed.
Best Practices
- Require strong, unique passwords
- Implement multi-factor authentication
- Use rate limiting on login endpoints
- Monitor for automated login patterns
Common Mistakes
- Relying solely on password complexity rules
- Not implementing account lockout after failed attempts
- Using the same error message for "user not found" and "wrong password" (enables enumeration)
How ShieldKey Helps
ShieldKey protects its own login with Argon2id hashing, rate limiting, and WebAuthn passkey support. For API keys, Shield Tokens are randomly generated — not derived from user passwords — making them immune to credential stuffing.
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How does credential stuffing work?
Attackers use leaked username/password combinations from past breaches and try them on other services. Automated tools can test millions of credentials per hour.