On Monday 17 April 2023 at 18:08 UTC, a carpet-bombing UDP flood targeted a education platform customer in the Nordics. The attack peaked at 253.7 Gbps and lasted 114 minutes. Traffic originated from 2289 autonomous systems in 36 countries, predominantly residential proxy networks.
| Vector | carpet-bombing UDP flood |
| Peak | 253.7 Gbps |
| Duration | 114 min |
| Time to mitigation | 0.475 s |
| Attack traffic reaching origin | 0.044% |
| Legitimate traffic challenged | 0.53% |
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 25 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.
- Add a dedicated rate limit for the targeted route.
- Enable authenticated origin pulls.
How does the proof-of-work challenge behave on older Android devices? Any numbers below Android 10?
The point about origin IPs leaking through certificate transparency logs is underrated.