On Wednesday 3 July 2024 at 12:50 UTC, a TLS handshake exhaustion targeted a fashion retail customer in Central Europe. The attack peaked at 889.9 million requests per second and lasted 101 minutes. Traffic originated from 2321 autonomous systems in 21 countries, predominantly residential proxy networks.
| Vector | TLS handshake exhaustion |
| Peak | 889.9 million requests per second |
| Duration | 101 min |
| Time to mitigation | 0.112 s |
| Attack traffic reaching origin | 0.088% |
| Legitimate traffic challenged | 0.10% |
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 631 within 8 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.
- Add a dedicated rate limit for the targeted route.