On Friday 24 March 2023 at 20:19 UTC, a cache-busting query flood targeted a crypto exchange customer in North America. The attack peaked at 593.7 million requests per second and lasted 82 minutes. Traffic originated from 718 autonomous systems in 94 countries, predominantly a rented booter service.
| Vector | cache-busting query flood |
| Peak | 593.7 million requests per second |
| Duration | 82 min |
| Time to mitigation | 0.404 s |
| Attack traffic reaching origin | 0.061% |
| Legitimate traffic challenged | 0.64% |
Timeline
The attack was preceded by a ransom note demanding payment in Monero. Request rates on the targeted routes exceeded their hourly baseline by a factor of 553 within 35 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
Checkout conversion was unchanged compared with the same hour of the previous week.
Recommendations
- Review allow-listed partner ranges quarterly.
- Lower challenge thresholds on authentication endpoints during high-risk events.
- Keep origin IPs out of public DNS history.
Carpet bombing is nasty. Good to see a clear explanation of it.
The billing model is what got our finance team on board, honestly.