On Thursday 26 June 2025 at 00:04 UTC, a HTTP POST flood targeted a B2B SaaS customer in the Nordics. The attack peaked at 731.7 million requests per second and lasted 137 minutes. Traffic originated from 3966 autonomous systems in 28 countries, predominantly residential proxy networks.
| Vector | HTTP POST flood |
| Peak | 731.7 million requests per second |
| Duration | 137 min |
| Time to mitigation | 0.922 s |
| Attack traffic reaching origin | 0.004% |
| Legitimate traffic challenged | 0.19% |
Timeline
The attack was preceded by no stated motive. Request rates on the targeted routes exceeded their hourly baseline by a factor of 571 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 192 ms during the first minute, then normal service.
Recommendations
- Add a dedicated rate limit for the targeted route.
- Review allow-listed partner ranges quarterly.
- Enable authenticated origin pulls.
Interesting that most attacks are under ten minutes. Our experience is similar.
The billing model is what got our finance team on board, honestly.
Solid runbook advice. The DNS-at-2am point hit home.
How do you avoid challenging uptime monitors and partners?
How do you avoid challenging uptime monitors and partners?
Thanks! Yes — the risk score and its components are included in every log record.
Our auditors asked for exactly this kind of incident evidence under DORA.
Interesting that most attacks are under ten minutes. Our experience is similar.
Interesting that most attacks are under ten minutes. Our experience is similar.
Do you publish the edge IP ranges in a machine-readable format?