On Saturday 21 October 2023 at 03:42 UTC, a UDP reflection (DNS) targeted a developer platform customer in Iberia. The attack peaked at 37.6 Gbps and lasted 52 minutes. Traffic originated from 4090 autonomous systems in 39 countries, predominantly misconfigured open reflectors.
| Vector | UDP reflection (DNS) |
| Peak | 37.6 Gbps |
| Duration | 52 min |
| Time to mitigation | 0.294 s |
| Attack traffic reaching origin | 0.060% |
| Legitimate traffic challenged | 0.73% |
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
The customer’s status page stayed green throughout; they learned about the attack from our notification.
Recommendations
- Add a dedicated rate limit for the targeted route.
- Review allow-listed partner ranges quarterly.
- Enable authenticated origin pulls.
Solid runbook advice. The DNS-at-2am point hit home.
Thanks! Yes — the risk score and its components are included in every log record.
How does the proof-of-work challenge behave on older Android devices? Any numbers below Android 10?
Could you share the dataset behind the percentages?
Verified good bots and allow-listed partners bypass challenges entirely.
We had the exact false-positive issue with CGNAT carriers. The weighting change makes sense.
Clear and practical, thanks.