On Wednesday 22 June 2022 at 10:23 UTC, a ACK flood targeted a healthcare portal customer in Central Europe. The attack peaked at 87.5 Gbps and lasted 67 minutes. Traffic originated from 316 autonomous systems in 113 countries, predominantly a headless-browser farm.
| Vector | ACK flood |
| Peak | 87.5 Gbps |
| Duration | 67 min |
| Time to mitigation | 0.284 s |
| Attack traffic reaching origin | 0.000% |
| Legitimate traffic challenged | 0.01% |
Timeline
The attack was preceded by a hacktivist channel announcing the target. Edge packet filters identified the flood by source port and payload signature and dropped it at line rate across 33 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
- Add a dedicated rate limit for the targeted route.
- Keep origin IPs out of public DNS history.
- Enable authenticated origin pulls.
Solid runbook advice. The DNS-at-2am point hit home.
This matches what we see in iGaming around big matches.
The billing model is what got our finance team on board, honestly.
Nice to read a vendor blog that admits what went wrong.
Machine-readable ranges are at /ips.json and via the API.
Clear and practical, thanks.
The point about origin IPs leaking through certificate transparency logs is underrated.
Do you publish the edge IP ranges in a machine-readable format?
Could you share the dataset behind the percentages?
We had the exact false-positive issue with CGNAT carriers. The weighting change makes sense.