On Sunday 21 July 2024 at 16:46 UTC, a ACK flood targeted a video streaming customer in North America. The attack peaked at 326.2 Gbps and lasted 137 minutes. Traffic originated from 876 autonomous systems in 52 countries, predominantly a Mirai-derived IoT botnet.
| Vector | ACK flood |
| Peak | 326.2 Gbps |
| Duration | 137 min |
| Time to mitigation | 0.920 s |
| Attack traffic reaching origin | 0.015% |
| Legitimate traffic challenged | 0.37% |
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 13 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.
- Enable authenticated origin pulls.
Solid runbook advice. The DNS-at-2am point hit home.
Would love a follow-up on how you handle HTTP/3 fingerprinting.
Could you share the dataset behind the percentages?
Verified good bots and allow-listed partners bypass challenges entirely.
Carpet bombing is nasty. Good to see a clear explanation of it.
We moved from a scrubbing provider to always-on last year; time to mitigation went from minutes to basically nothing.
Thanks — sharing this with our on-call team.
Great to hear, thanks for sharing your experience.