On Saturday 2 October 2021 at 15:59 UTC, a HTTP GET flood targeted a news publisher customer in Western Europe. The attack peaked at 773.0 million requests per second and lasted 178 minutes. Traffic originated from 937 autonomous systems in 57 countries, predominantly misconfigured open reflectors.
| Vector | HTTP GET flood |
| Peak | 773.0 million requests per second |
| Duration | 178 min |
| Time to mitigation | 0.112 s |
| Attack traffic reaching origin | 0.041% |
| Legitimate traffic challenged | 0.17% |
Timeline
The attack was preceded by a competitor’s product launch. Request rates on the targeted routes exceeded their hourly baseline by a factor of 424 within 40 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
- Enable authenticated origin pulls.
- Review allow-listed partner ranges quarterly.
- Keep origin IPs out of public DNS history.
This matches what we see in iGaming around big matches.
Our auditors asked for exactly this kind of incident evidence under DORA.
The billing model is what got our finance team on board, honestly.