On Sunday 14 April 2024 at 00:15 UTC, a search endpoint flood targeted a ticketing customer in North America. The attack peaked at 957.7 million requests per second and lasted 63 minutes. Traffic originated from 182 autonomous systems in 52 countries, predominantly a Mirai-derived IoT botnet.
| Vector | search endpoint flood |
| Peak | 957.7 million requests per second |
| Duration | 63 min |
| Time to mitigation | 0.083 s |
| Attack traffic reaching origin | 0.062% |
| Legitimate traffic challenged | 0.44% |
Timeline
The attack was preceded by an extortion email received two days earlier. Request rates on the targeted routes exceeded their hourly baseline by a factor of 643 within 17 seconds. The risk score of participating clients crossed the challenge threshold automatically and proof-of-work difficulty rose with origin load.
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.
- Lower challenge thresholds on authentication endpoints during high-risk events.
- Keep origin IPs out of public DNS history.
Thanks — sharing this with our on-call team.
Machine-readable ranges are at /ips.json and via the API.
Carpet bombing is nasty. Good to see a clear explanation of it.
We moved from a scrubbing provider to always-on last year; time to mitigation went from minutes to basically nothing.
Thanks — sharing this with our on-call team.
Solid runbook advice. The DNS-at-2am point hit home.
Interesting that most attacks are under ten minutes. Our experience is similar.
The point about origin IPs leaking through certificate transparency logs is underrated.
Thanks — sharing this with our on-call team.
Verified good bots and allow-listed partners bypass challenges entirely.