On Sunday 21 December 2025 at 14:20 UTC, a ACK flood targeted a ticketing customer in the Benelux. The attack peaked at 258.9 Gbps and lasted 186 minutes. Traffic originated from 4160 autonomous systems in 110 countries, predominantly a headless-browser farm.
| Vector | ACK flood |
| Peak | 258.9 Gbps |
| Duration | 186 min |
| Time to mitigation | 0.120 s |
| Attack traffic reaching origin | 0.062% |
| Legitimate traffic challenged | 0.21% |
Timeline
The attack was preceded by no stated motive. Edge packet filters identified the flood by source port and payload signature and dropped it at line rate across 16 points of presence.
What the customer saw
Checkout conversion was unchanged compared with the same hour of the previous week.
Recommendations
- Enable log streaming to your SIEM for faster correlation.
- Review allow-listed partner ranges quarterly.
- Add a dedicated rate limit for the targeted route.
Carpet bombing is nasty. Good to see a clear explanation of it.