On Tuesday 3 January 2023 at 01:57 UTC, a UDP reflection (NTP) targeted a education platform customer in the Nordics. The attack peaked at 282.5 Gbps and lasted 38 minutes. Traffic originated from 2064 autonomous systems in 58 countries, predominantly compromised cloud VMs.
| Vector | UDP reflection (NTP) |
| Peak | 282.5 Gbps |
| Duration | 38 min |
| Time to mitigation | 0.876 s |
| Attack traffic reaching origin | 0.018% |
| Legitimate traffic challenged | 0.79% |
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 25 points of presence.
What the customer saw
A brief increase in p99 latency of 50 ms during the first minute, then normal service.
Recommendations
- Lower challenge thresholds on authentication endpoints during high-risk events.
- Keep origin IPs out of public DNS history.
- Review allow-listed partner ranges quarterly.
Clear and practical, thanks.
The billing model is what got our finance team on board, honestly.
Clear and practical, thanks.
Would love a follow-up on how you handle HTTP/3 fingerprinting.
The point about origin IPs leaking through certificate transparency logs is underrated.