On Thursday 23 June 2022 at 20:38 UTC, a TLS handshake exhaustion targeted a B2B SaaS customer in Latin America. The attack peaked at 911.0 million requests per second and lasted 112 minutes. Traffic originated from 681 autonomous systems in 52 countries, predominantly a headless-browser farm.
| Vector | TLS handshake exhaustion |
| Peak | 911.0 million requests per second |
| Duration | 112 min |
| Time to mitigation | 0.441 s |
| Attack traffic reaching origin | 0.007% |
| Legitimate traffic challenged | 0.25% |
Timeline
The attack was preceded by a ransom note demanding payment in Monero. Request rates on the targeted routes exceeded their hourly baseline by a factor of 659 within 27 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
- Review allow-listed partner ranges quarterly.
- Enable authenticated origin pulls.
- Enable log streaming to your SIEM for faster correlation.
Do you publish the edge IP ranges in a machine-readable format?
Machine-readable ranges are at /ips.json and via the API.
The billing model is what got our finance team on board, honestly.
The billing model is what got our finance team on board, honestly.
Great to hear, thanks for sharing your experience.
Would love a follow-up on how you handle HTTP/3 fingerprinting.
Thanks — sharing this with our on-call team.
Could you share the dataset behind the percentages?
Thanks! Yes — the risk score and its components are included in every log record.
We moved from a scrubbing provider to always-on last year; time to mitigation went from minutes to basically nothing.