On Thursday 14 April 2022 at 01:24 UTC, a ACK flood targeted a fashion retail customer in the Benelux. The attack peaked at 104.5 Gbps and lasted 172 minutes. Traffic originated from 3680 autonomous systems in 21 countries, predominantly a headless-browser farm.
| Vector | ACK flood |
| Peak | 104.5 Gbps |
| Duration | 172 min |
| Time to mitigation | 0.492 s |
| Attack traffic reaching origin | 0.044% |
| Legitimate traffic challenged | 0.12% |
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 40 points of presence.
What the customer saw
Checkout conversion was unchanged compared with the same hour of the previous week.
Recommendations
- Add a dedicated rate limit for the targeted route.
- Enable log streaming to your SIEM for faster correlation.
- Keep origin IPs out of public DNS history.
The billing model is what got our finance team on board, honestly.
Thanks! Yes — the risk score and its components are included in every log record.
The billing model is what got our finance team on board, honestly.
Nice to read a vendor blog that admits what went wrong.
Do you publish the edge IP ranges in a machine-readable format?
Clear and practical, thanks.
Verified good bots and allow-listed partners bypass challenges entirely.