On Wednesday 1 October 2025 at 00:14 UTC, a login endpoint flood targeted a tax authority portal customer in the Nordics. The attack peaked at 373.5 million requests per second and lasted 125 minutes. Traffic originated from 1853 autonomous systems in 105 countries, predominantly hijacked home routers.
| Vector | login endpoint flood |
| Peak | 373.5 million requests per second |
| Duration | 125 min |
| Time to mitigation | 0.106 s |
| Attack traffic reaching origin | 0.000% |
| Legitimate traffic challenged | 0.49% |
Timeline
The attack was preceded by a hacktivist channel announcing the target. Request rates on the targeted routes exceeded their hourly baseline by a factor of 599 within 9 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
- Enable authenticated origin pulls.
- Keep origin IPs out of public DNS history.
- Add a dedicated rate limit for the targeted route.
Our auditors asked for exactly this kind of incident evidence under DORA.
Carpet bombing is nasty. Good to see a clear explanation of it.