On Tuesday 26 March 2024 at 04:58 UTC, a UDP reflection (DNS) targeted a education platform customer in Southeast Asia. The attack peaked at 376.5 Gbps and lasted 13 minutes. Traffic originated from 1537 autonomous systems in 62 countries, predominantly misconfigured open reflectors.
| Vector | UDP reflection (DNS) |
| Peak | 376.5 Gbps |
| Duration | 13 min |
| Time to mitigation | 0.541 s |
| Attack traffic reaching origin | 0.025% |
| Legitimate traffic challenged | 0.38% |
Timeline
The attack was preceded by a competitor’s product launch. Edge packet filters identified the flood by source port and payload signature and dropped it at line rate across 26 points of presence.
What the customer saw
The customer’s status page stayed green throughout; they learned about the attack from our notification.
Recommendations
- Enable authenticated origin pulls.
- Review allow-listed partner ranges quarterly.
- Lower challenge thresholds on authentication endpoints during high-risk events.
Solid runbook advice. The DNS-at-2am point hit home.
How does the proof-of-work challenge behave on older Android devices? Any numbers below Android 10?
Interesting that most attacks are under ten minutes. Our experience is similar.
Machine-readable ranges are at /ips.json and via the API.
Do you publish the edge IP ranges in a machine-readable format?
Clear and practical, thanks.
How does the proof-of-work challenge behave on older Android devices? Any numbers below Android 10?
Thanks! Yes — the risk score and its components are included in every log record.
Thanks — sharing this with our on-call team.
Thanks! Yes — the risk score and its components are included in every log record.
Is the risk score exposed in the logs so we can build our own dashboards on it?
Could you share the dataset behind the percentages?