On Wednesday 24 January 2024 at 23:28 UTC, a WebSocket connection flood targeted a retail banking customer in the Middle East. The attack peaked at 200.5 million requests per second and lasted 99 minutes. Traffic originated from 3951 autonomous systems in 85 countries, predominantly mobile carrier ranges.
| Vector | WebSocket connection flood |
| Peak | 200.5 million requests per second |
| Duration | 99 min |
| Time to mitigation | 0.495 s |
| Attack traffic reaching origin | 0.066% |
| Legitimate traffic challenged | 0.36% |
Timeline
The attack was preceded by a breaking political story. Request rates on the targeted routes exceeded their hourly baseline by a factor of 745 within 28 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
A brief increase in p99 latency of 226 ms during the first minute, then normal service.
Recommendations
- Lower challenge thresholds on authentication endpoints during high-risk events.
- Add a dedicated rate limit for the targeted route.
- Keep origin IPs out of public DNS history.