On Thursday 11 August 2022 at 14:43 UTC, a cache-busting query flood targeted a crypto exchange customer in North America. The attack peaked at 607.7 million requests per second and lasted 137 minutes. Traffic originated from 1215 autonomous systems in 11 countries, predominantly misconfigured open reflectors.
| Vector | cache-busting query flood |
| Peak | 607.7 million requests per second |
| Duration | 137 min |
| Time to mitigation | 0.113 s |
| Attack traffic reaching origin | 0.021% |
| Legitimate traffic challenged | 0.79% |
Timeline
The attack was preceded by a publicly announced sales event. Request rates on the targeted routes exceeded their hourly baseline by a factor of 549 within 34 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
No customer-visible impact. The on-call engineer was notified and acknowledged the incident from the dashboard.
Recommendations
- Keep origin IPs out of public DNS history.
- Add a dedicated rate limit for the targeted route.
- Enable log streaming to your SIEM for faster correlation.