On Friday 16 June 2023 at 09:10 UTC, a credential stuffing targeted a education platform customer in Central Europe. The attack peaked at 341.8 million requests per second and lasted 167 minutes. Traffic originated from 3780 autonomous systems in 101 countries, predominantly misconfigured open reflectors.
| Vector | credential stuffing |
| Peak | 341.8 million requests per second |
| Duration | 167 min |
| Time to mitigation | 0.723 s |
| Attack traffic reaching origin | 0.052% |
| Legitimate traffic challenged | 0.30% |
Timeline
The attack was preceded by a breaking political story. Request rates on the targeted routes exceeded their hourly baseline by a factor of 551 within 7 seconds. The risk score of participating clients crossed the challenge threshold automatically and proof-of-work difficulty rose with origin load.
What the customer saw
The customer’s status page stayed green throughout; they learned about the attack from our notification.
Recommendations
- Keep origin IPs out of public DNS history.
- Lower challenge thresholds on authentication endpoints during high-risk events.
- Enable authenticated origin pulls.
Clear and practical, thanks.