On Tuesday 1 February 2022 at 13:12 UTC, a WebSocket connection flood targeted a electronics retail customer in Iberia. The attack peaked at 976.4 million requests per second and lasted 92 minutes. Traffic originated from 3143 autonomous systems in 59 countries, predominantly a headless-browser farm.
| Vector | WebSocket connection flood |
| Peak | 976.4 million requests per second |
| Duration | 92 min |
| Time to mitigation | 0.407 s |
| Attack traffic reaching origin | 0.007% |
| Legitimate traffic challenged | 0.48% |
Timeline
The attack was preceded by a ransom note demanding payment in Monero. Request rates on the targeted routes exceeded their hourly baseline by a factor of 505 within 34 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
- Add a dedicated rate limit for the targeted route.
- Keep origin IPs out of public DNS history.
- Review allow-listed partner ranges quarterly.
Carpet bombing is nasty. Good to see a clear explanation of it.
We moved from a scrubbing provider to always-on last year; time to mitigation went from minutes to basically nothing.
Solid runbook advice. The DNS-at-2am point hit home.
Would love a follow-up on how you handle HTTP/3 fingerprinting.
Verified good bots and allow-listed partners bypass challenges entirely.
Could you share the dataset behind the percentages?