Credential stuffing is one of the most common and damaging forms of automated attacks. Here's what you need to know.
What is Credential Stuffing?
When data breaches expose username/password combinations, attackers use bots to test those credentials on other sites. Since many people reuse passwords, this is surprisingly effective.
The Scale of the Problem
- Billions of credentials are available on the dark web
- Automated tools can test thousands of logins per second
- Success rates of 0.1-2% are common—and profitable
How to Protect Your Users
Rate Limiting
Limit login attempts per IP and account. But be careful—attackers rotate IPs.
Bot Detection
Use behavioral analysis to identify automated login attempts. This is where Shilish excels.
Breach Detection
Check passwords against known breached credentials and require changes when matches are found.
Multi-Factor Authentication
MFA stops credential stuffing cold. Even with valid credentials, attackers can't complete the second factor.