On Saturday 9 December 2023 at 05:09 UTC, a HTTP POST flood targeted a municipal services customer in Southeast Asia. The attack peaked at 690.2 million requests per second and lasted 151 minutes. Traffic originated from 1214 autonomous systems in 114 countries, predominantly mobile carrier ranges.
| Vector | HTTP POST flood |
| Peak | 690.2 million requests per second |
| Duration | 151 min |
| Time to mitigation | 0.166 s |
| Attack traffic reaching origin | 0.016% |
| Legitimate traffic challenged | 0.43% |
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 748 within 10 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
The customer’s status page stayed green throughout; they learned about the attack from our notification.
Recommendations
- Lower challenge thresholds on authentication endpoints during high-risk events.
- Add a dedicated rate limit for the targeted route.
- Enable authenticated origin pulls.