On Monday 4 May 2026 at 21:10 UTC, a ACK flood targeted a video streaming customer in North America. The attack peaked at 18.8 Gbps and lasted 147 minutes. Traffic originated from 992 autonomous systems in 6 countries, predominantly hijacked home routers.
| Vector | ACK flood |
| Peak | 18.8 Gbps |
| Duration | 147 min |
| Time to mitigation | 0.310 s |
| Attack traffic reaching origin | 0.051% |
| Legitimate traffic challenged | 0.19% |
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 36 points of presence.
What the customer saw
A brief increase in p99 latency of 218 ms during the first minute, then normal service.
Recommendations
- Enable authenticated origin pulls.
- Review allow-listed partner ranges quarterly.
- Add a dedicated rate limit for the targeted route.
Interesting that most attacks are under ten minutes. Our experience is similar.
The point about origin IPs leaking through certificate transparency logs is underrated.
Do you publish the edge IP ranges in a machine-readable format?