On Friday 17 November 2023 at 21:41 UTC, a SYN flood targeted a video streaming customer in North America. The attack peaked at 104.7 Gbps and lasted 95 minutes. Traffic originated from 3480 autonomous systems in 84 countries, predominantly mobile carrier ranges.
| Vector | SYN flood |
| Peak | 104.7 Gbps |
| Duration | 95 min |
| Time to mitigation | 0.689 s |
| Attack traffic reaching origin | 0.000% |
| Legitimate traffic challenged | 0.63% |
Timeline
The attack was preceded by a breaking political story. Edge packet filters identified the flood by source port and payload signature and dropped it at line rate across 28 points of presence.
What the customer saw
The customer’s status page stayed green throughout; they learned about the attack from our notification.
Recommendations
- Keep origin IPs out of public DNS history.
- Enable log streaming to your SIEM for faster correlation.
- Review allow-listed partner ranges quarterly.
Our auditors asked for exactly this kind of incident evidence under DORA.
Thanks! Yes — the risk score and its components are included in every log record.
Is the risk score exposed in the logs so we can build our own dashboards on it?
Great write-up. We saw almost the same pattern on our login endpoint last month.
Do you publish the edge IP ranges in a machine-readable format?
Clear and practical, thanks.
We moved from a scrubbing provider to always-on last year; time to mitigation went from minutes to basically nothing.
Nice to read a vendor blog that admits what went wrong.
Do you publish the edge IP ranges in a machine-readable format?
Great write-up. We saw almost the same pattern on our login endpoint last month.