On Sunday 24 April 2022 at 19:58 UTC, a credential stuffing targeted a electronics retail customer in Western Europe. The attack peaked at 304.6 million requests per second and lasted 48 minutes. Traffic originated from 2359 autonomous systems in 81 countries, predominantly compromised cloud VMs.
| Vector | credential stuffing |
| Peak | 304.6 million requests per second |
| Duration | 48 min |
| Time to mitigation | 0.441 s |
| Attack traffic reaching origin | 0.066% |
| Legitimate traffic challenged | 0.52% |
Timeline
The attack was preceded by no stated motive. Request rates on the targeted routes exceeded their hourly baseline by a factor of 233 within 39 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
No customer-visible impact. The on-call engineer was notified and acknowledged the incident from the dashboard.
Recommendations
- Keep origin IPs out of public DNS history.
- Review allow-listed partner ranges quarterly.
- Enable log streaming to your SIEM for faster correlation.
The billing model is what got our finance team on board, honestly.