On Saturday 17 August 2024 at 22:18 UTC, a UDP reflection (NTP) targeted a tax authority portal customer in Western Europe. The attack peaked at 87.2 Gbps and lasted 61 minutes. Traffic originated from 3537 autonomous systems in 13 countries, predominantly misconfigured open reflectors.
| Vector | UDP reflection (NTP) |
| Peak | 87.2 Gbps |
| Duration | 61 min |
| Time to mitigation | 0.930 s |
| Attack traffic reaching origin | 0.047% |
| Legitimate traffic challenged | 0.54% |
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 39 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
- Review allow-listed partner ranges quarterly.
- Keep origin IPs out of public DNS history.
- Enable authenticated origin pulls.
This matches what we see in iGaming around big matches.
Verified good bots and allow-listed partners bypass challenges entirely.
Clear and practical, thanks.
Nice to read a vendor blog that admits what went wrong.
Interesting that most attacks are under ten minutes. Our experience is similar.