On Wednesday 25 December 2024 at 09:19 UTC, a TLS handshake exhaustion targeted a online casino customer in Southeast Asia. The attack peaked at 434.6 million requests per second and lasted 39 minutes. Traffic originated from 406 autonomous systems in 85 countries, predominantly misconfigured open reflectors.
| Vector | TLS handshake exhaustion |
| Peak | 434.6 million requests per second |
| Duration | 39 min |
| Time to mitigation | 0.633 s |
| Attack traffic reaching origin | 0.036% |
| Legitimate traffic challenged | 0.20% |
Timeline
The attack was preceded by a breaking political story. Request rates on the targeted routes exceeded their hourly baseline by a factor of 757 within 12 seconds. The risk score of participating clients crossed the challenge threshold automatically and proof-of-work difficulty rose with origin load.
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.