On Monday 6 February 2023 at 20:03 UTC, a HTTP GET flood targeted a municipal services customer in Central Europe. The attack peaked at 940.8 million requests per second and lasted 68 minutes. Traffic originated from 3409 autonomous systems in 14 countries, predominantly compromised cloud VMs.
| Vector | HTTP GET flood |
| Peak | 940.8 million requests per second |
| Duration | 68 min |
| Time to mitigation | 0.812 s |
| Attack traffic reaching origin | 0.063% |
| Legitimate traffic challenged | 0.75% |
Timeline
The attack was preceded by an extortion email received two days earlier. Request rates on the targeted routes exceeded their hourly baseline by a factor of 542 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.
- Keep origin IPs out of public DNS history.
- Enable authenticated origin pulls.