On Wednesday 24 September 2025 at 02:27 UTC, a UDP reflection (DNS) targeted a retail banking customer in Iberia. The attack peaked at 281.8 Gbps and lasted 134 minutes. Traffic originated from 2728 autonomous systems in 64 countries, predominantly misconfigured open reflectors.
| Vector | UDP reflection (DNS) |
| Peak | 281.8 Gbps |
| Duration | 134 min |
| Time to mitigation | 0.788 s |
| Attack traffic reaching origin | 0.056% |
| Legitimate traffic challenged | 0.15% |
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 24 points of presence.
What the customer saw
Checkout conversion was unchanged compared with the same hour of the previous week.
Recommendations
- Enable authenticated origin pulls.
- Review allow-listed partner ranges quarterly.
- Keep origin IPs out of public DNS history.
We had the exact false-positive issue with CGNAT carriers. The weighting change makes sense.
Carpet bombing is nasty. Good to see a clear explanation of it.
Any plans to support per-tenant limits keyed on a JWT claim?
Would love a follow-up on how you handle HTTP/3 fingerprinting.