On Sunday 21 March 2021 at 22:07 UTC, a Slowloris targeted a airline booking customer in the Middle East. The attack peaked at 815.4 million requests per second and lasted 79 minutes. Traffic originated from 3491 autonomous systems in 68 countries, predominantly hijacked home routers.
| Vector | Slowloris |
| Peak | 815.4 million requests per second |
| Duration | 79 min |
| Time to mitigation | 0.921 s |
| Attack traffic reaching origin | 0.086% |
| Legitimate traffic challenged | 0.23% |
Timeline
The attack was preceded by no stated motive. Request rates on the targeted routes exceeded their hourly baseline by a factor of 400 within 6 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.
- Lower challenge thresholds on authentication endpoints during high-risk events.
- Add a dedicated rate limit for the targeted route.