On Sunday 25 July 2021 at 08:48 UTC, a UDP reflection (NTP) targeted a gaming community customer in the Nordics. The attack peaked at 180.6 Gbps and lasted 160 minutes. Traffic originated from 2389 autonomous systems in 93 countries, predominantly mobile carrier ranges.
| Vector | UDP reflection (NTP) |
| Peak | 180.6 Gbps |
| Duration | 160 min |
| Time to mitigation | 0.061 s |
| Attack traffic reaching origin | 0.031% |
| Legitimate traffic challenged | 0.20% |
Timeline
The attack was preceded by a breaking political story. Edge packet filters identified the flood by source port and payload signature and dropped it at line rate across 13 points of presence.
What the customer saw
A brief increase in p99 latency of 206 ms during the first minute, then normal service.
Recommendations
- Enable log streaming to your SIEM for faster correlation.
- Add a dedicated rate limit for the targeted route.
- Keep origin IPs out of public DNS history.