On Sunday 15 March 2026 at 04:35 UTC, a WebSocket connection flood targeted a developer platform customer in Iberia. The attack peaked at 876.7 million requests per second and lasted 111 minutes. Traffic originated from 1097 autonomous systems in 31 countries, predominantly a Mirai-derived IoT botnet.
| Vector | WebSocket connection flood |
| Peak | 876.7 million requests per second |
| Duration | 111 min |
| Time to mitigation | 0.018 s |
| Attack traffic reaching origin | 0.075% |
| Legitimate traffic challenged | 0.03% |
Timeline
The attack was preceded by a publicly announced sales event. Request rates on the targeted routes exceeded their hourly baseline by a factor of 615 within 38 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
- Enable log streaming to your SIEM for faster correlation.
- Review allow-listed partner ranges quarterly.
- Add a dedicated rate limit for the targeted route.
How does the proof-of-work challenge behave on older Android devices? Any numbers below Android 10?
Clear and practical, thanks.
Thanks — sharing this with our on-call team.