On Thursday 16 November 2023 at 07:20 UTC, a UDP reflection (NTP) targeted a sports betting customer in Central Europe. The attack peaked at 243.9 Gbps and lasted 137 minutes. Traffic originated from 1901 autonomous systems in 98 countries, predominantly a rented booter service.
| Vector | UDP reflection (NTP) |
| Peak | 243.9 Gbps |
| Duration | 137 min |
| Time to mitigation | 0.510 s |
| Attack traffic reaching origin | 0.066% |
| Legitimate traffic challenged | 0.19% |
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 33 points of presence.
What the customer saw
A brief increase in p99 latency of 126 ms during the first minute, then normal service.
Recommendations
- Keep origin IPs out of public DNS history.
- Add a dedicated rate limit for the targeted route.
- Enable authenticated origin pulls.
Do you publish the edge IP ranges in a machine-readable format?
Good question. We will cover that in a follow-up post.
Nice to read a vendor blog that admits what went wrong.
Thanks! Yes — the risk score and its components are included in every log record.