On Monday 21 October 2024 at 22:10 UTC, a SYN flood targeted a online casino customer in the UK. The attack peaked at 339.0 Gbps and lasted 35 minutes. Traffic originated from 3538 autonomous systems in 88 countries, predominantly a headless-browser farm.
| Vector | SYN flood |
| Peak | 339.0 Gbps |
| Duration | 35 min |
| Time to mitigation | 0.773 s |
| Attack traffic reaching origin | 0.063% |
| Legitimate traffic challenged | 0.46% |
Timeline
The attack was preceded by a competitor’s product launch. 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
- Lower challenge thresholds on authentication endpoints during high-risk events.
- Keep origin IPs out of public DNS history.
- Enable authenticated origin pulls.
This matches what we see in iGaming around big matches.
Interesting that most attacks are under ten minutes. Our experience is similar.