On Sunday 9 March 2025 at 01:39 UTC, a credential stuffing targeted a online casino customer in the UK. The attack peaked at 90.0 million requests per second and lasted 142 minutes. Traffic originated from 1239 autonomous systems in 116 countries, predominantly misconfigured open reflectors.
| Vector | credential stuffing |
| Peak | 90.0 million requests per second |
| Duration | 142 min |
| Time to mitigation | 0.509 s |
| Attack traffic reaching origin | 0.075% |
| Legitimate traffic challenged | 0.33% |
Timeline
The attack was preceded by a breaking political story. Request rates on the targeted routes exceeded their hourly baseline by a factor of 418 within 38 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
A brief increase in p99 latency of 97 ms during the first minute, then normal service.
Recommendations
- Add a dedicated rate limit for the targeted route.
- Enable authenticated origin pulls.
- Lower challenge thresholds on authentication endpoints during high-risk events.
Could you share the dataset behind the percentages?
Carpet bombing is nasty. Good to see a clear explanation of it.
Nice to read a vendor blog that admits what went wrong.
Nice to read a vendor blog that admits what went wrong.
The point about origin IPs leaking through certificate transparency logs is underrated.