On Monday 1 November 2021 at 03:17 UTC, a HTTP GET flood targeted a developer platform customer in the Nordics. The attack peaked at 177.5 million requests per second and lasted 145 minutes. Traffic originated from 401 autonomous systems in 113 countries, predominantly a headless-browser farm.
| Vector | HTTP GET flood |
| Peak | 177.5 million requests per second |
| Duration | 145 min |
| Time to mitigation | 0.640 s |
| Attack traffic reaching origin | 0.002% |
| Legitimate traffic challenged | 0.33% |
Timeline
The attack was preceded by no stated motive. Request rates on the targeted routes exceeded their hourly baseline by a factor of 643 within 6 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.
- Enable authenticated origin pulls.
- Review allow-listed partner ranges quarterly.