On Wednesday 2 October 2024 at 18:37 UTC, a TLS handshake exhaustion targeted a video streaming customer in Central Europe. The attack peaked at 80.1 million requests per second and lasted 159 minutes. Traffic originated from 1206 autonomous systems in 74 countries, predominantly mobile carrier ranges.
| Vector | TLS handshake exhaustion |
| Peak | 80.1 million requests per second |
| Duration | 159 min |
| Time to mitigation | 0.740 s |
| Attack traffic reaching origin | 0.009% |
| Legitimate traffic challenged | 0.73% |
Timeline
The attack was preceded by an extortion email received two days earlier. Request rates on the targeted routes exceeded their hourly baseline by a factor of 830 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
- Lower challenge thresholds on authentication endpoints during high-risk events.
- Review allow-listed partner ranges quarterly.
- Enable authenticated origin pulls.