On Friday 19 November 2021 at 19:50 UTC, a UDP reflection (NTP) targeted a online casino customer in Southeast Asia. The attack peaked at 121.7 Gbps and lasted 52 minutes. Traffic originated from 2248 autonomous systems in 86 countries, predominantly a Mirai-derived IoT botnet.
| Vector | UDP reflection (NTP) |
| Peak | 121.7 Gbps |
| Duration | 52 min |
| Time to mitigation | 0.906 s |
| Attack traffic reaching origin | 0.021% |
| Legitimate traffic challenged | 0.34% |
Timeline
The attack was preceded by no stated motive. Edge packet filters identified the flood by source port and payload signature and dropped it at line rate across 20 points of presence.
What the customer saw
No customer-visible impact. The on-call engineer was notified and acknowledged the incident from the dashboard.
Recommendations
- Add a dedicated rate limit for the targeted route.
- Lower challenge thresholds on authentication endpoints during high-risk events.
- Enable authenticated origin pulls.