On Monday 20 November 2023 at 11:56 UTC, a Slowloris targeted a retail banking customer in the Middle East. The attack peaked at 22.4 million requests per second and lasted 181 minutes. Traffic originated from 1661 autonomous systems in 31 countries, predominantly mobile carrier ranges.
| Vector | Slowloris |
| Peak | 22.4 million requests per second |
| Duration | 181 min |
| Time to mitigation | 0.858 s |
| Attack traffic reaching origin | 0.064% |
| Legitimate traffic challenged | 0.16% |
Timeline
The attack was preceded by a competitor’s product launch. Request rates on the targeted routes exceeded their hourly baseline by a factor of 176 within 30 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 log streaming to your SIEM for faster correlation.
- Enable authenticated origin pulls.