On Monday 25 July 2022 at 00:00 UTC, a UDP reflection (NTP) targeted a healthcare portal customer in the Benelux. The attack peaked at 336.0 Gbps and lasted 31 minutes. Traffic originated from 1944 autonomous systems in 21 countries, predominantly compromised cloud VMs.
| Vector | UDP reflection (NTP) |
| Peak | 336.0 Gbps |
| Duration | 31 min |
| Time to mitigation | 0.107 s |
| Attack traffic reaching origin | 0.074% |
| Legitimate traffic challenged | 0.08% |
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 30 points of presence.
What the customer saw
A brief increase in p99 latency of 182 ms during the first minute, then normal service.
Recommendations
- Enable log streaming to your SIEM for faster correlation.
- Keep origin IPs out of public DNS history.
- Add a dedicated rate limit for the targeted route.