On Saturday 21 August 2021 at 14:49 UTC, a login endpoint flood targeted a electronics retail customer in the Nordics. The attack peaked at 684.6 million requests per second and lasted 185 minutes. Traffic originated from 2556 autonomous systems in 9 countries, predominantly a Mirai-derived IoT botnet.
| Vector | login endpoint flood |
| Peak | 684.6 million requests per second |
| Duration | 185 min |
| Time to mitigation | 0.377 s |
| Attack traffic reaching origin | 0.042% |
| Legitimate traffic challenged | 0.14% |
Timeline
The attack was preceded by a breaking political story. Request rates on the targeted routes exceeded their hourly baseline by a factor of 212 within 22 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
- Keep origin IPs out of public DNS history.
- Lower challenge thresholds on authentication endpoints during high-risk events.
- Review allow-listed partner ranges quarterly.