On Monday 11 April 2022 at 06:13 UTC, a HTTP GET flood targeted a fashion retail customer in the Benelux. The attack peaked at 536.0 million requests per second and lasted 96 minutes. Traffic originated from 617 autonomous systems in 85 countries, predominantly a Mirai-derived IoT botnet.
| Vector | HTTP GET flood |
| Peak | 536.0 million requests per second |
| Duration | 96 min |
| Time to mitigation | 0.459 s |
| Attack traffic reaching origin | 0.083% |
| Legitimate traffic challenged | 0.74% |
Timeline
The attack was preceded by a hacktivist channel announcing the target. Request rates on the targeted routes exceeded their hourly baseline by a factor of 529 within 25 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
- Lower challenge thresholds on authentication endpoints during high-risk events.
- Enable authenticated origin pulls.
- Add a dedicated rate limit for the targeted route.
Carpet bombing is nasty. Good to see a clear explanation of it.
Clear and practical, thanks.