On Thursday 18 March 2021 at 04:11 UTC, a ACK flood targeted a gaming community customer in Latin America. The attack peaked at 211.0 Gbps and lasted 36 minutes. Traffic originated from 1326 autonomous systems in 108 countries, predominantly a rented booter service.
| Vector | ACK flood |
| Peak | 211.0 Gbps |
| Duration | 36 min |
| Time to mitigation | 0.946 s |
| Attack traffic reaching origin | 0.039% |
| Legitimate traffic challenged | 0.69% |
Timeline
The attack was preceded by a hacktivist channel announcing the target. Edge packet filters identified the flood by source port and payload signature and dropped it at line rate across 25 points of presence.
What the customer saw
Checkout conversion was unchanged compared with the same hour of the previous week.
Recommendations
- Add a dedicated rate limit for the targeted route.
- 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.
Clear and practical, thanks.
Solid runbook advice. The DNS-at-2am point hit home.
Could you share the dataset behind the percentages?
Great write-up. We saw almost the same pattern on our login endpoint last month.
Is the risk score exposed in the logs so we can build our own dashboards on it?
Would love a follow-up on how you handle HTTP/3 fingerprinting.