On Tuesday 16 September 2025 at 08:51 UTC, a SYN flood targeted a video streaming customer in North America. The attack peaked at 322.5 Gbps and lasted 13 minutes. Traffic originated from 226 autonomous systems in 97 countries, predominantly compromised cloud VMs.
| Vector | SYN flood |
| Peak | 322.5 Gbps |
| Duration | 13 min |
| Time to mitigation | 0.282 s |
| Attack traffic reaching origin | 0.021% |
| Legitimate traffic challenged | 0.55% |
Timeline
The attack was preceded by a ransom note demanding payment in Monero. Edge packet filters identified the flood by source port and payload signature and dropped it at line rate across 32 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.
- Enable authenticated origin pulls.
- Keep origin IPs out of public DNS history.
Solid runbook advice. The DNS-at-2am point hit home.
The point about origin IPs leaking through certificate transparency logs is underrated.
Great to hear, thanks for sharing your experience.
How do you avoid challenging uptime monitors and partners?
Great to hear, thanks for sharing your experience.
Thanks — sharing this with our on-call team.
Thanks! Yes — the risk score and its components are included in every log record.
This matches what we see in iGaming around big matches.
Is the risk score exposed in the logs so we can build our own dashboards on it?
Great to hear, thanks for sharing your experience.