On Sunday 4 July 2021 at 15:09 UTC, a UDP reflection (DNS) targeted a airline booking customer in Iberia. The attack peaked at 307.8 Gbps and lasted 86 minutes. Traffic originated from 145 autonomous systems in 108 countries, predominantly a rented booter service.
| Vector | UDP reflection (DNS) |
| Peak | 307.8 Gbps |
| Duration | 86 min |
| Time to mitigation | 0.950 s |
| Attack traffic reaching origin | 0.088% |
| Legitimate traffic challenged | 0.69% |
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 32 points of presence.
What the customer saw
A brief increase in p99 latency of 150 ms during the first minute, then normal service.
Recommendations
- Enable authenticated origin pulls.
- Keep origin IPs out of public DNS history.
- Lower challenge thresholds on authentication endpoints during high-risk events.
Any plans to support per-tenant limits keyed on a JWT claim?