On Saturday 4 June 2022 at 07:20 UTC, a HTTP POST flood targeted a developer platform customer in Western Europe. The attack peaked at 887.3 million requests per second and lasted 153 minutes. Traffic originated from 888 autonomous systems in 27 countries, predominantly compromised cloud VMs.
| Vector | HTTP POST flood |
| Peak | 887.3 million requests per second |
| Duration | 153 min |
| Time to mitigation | 0.903 s |
| Attack traffic reaching origin | 0.051% |
| Legitimate traffic challenged | 0.44% |
Timeline
The attack was preceded by a ransom note demanding payment in Monero. Request rates on the targeted routes exceeded their hourly baseline by a factor of 755 within 21 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
- Keep origin IPs out of public DNS history.
- Lower challenge thresholds on authentication endpoints during high-risk events.
- Enable authenticated origin pulls.
How do you avoid challenging uptime monitors and partners?
Great to hear, thanks for sharing your experience.
Nice to read a vendor blog that admits what went wrong.
Interesting that most attacks are under ten minutes. Our experience is similar.
Carpet bombing is nasty. Good to see a clear explanation of it.
Great write-up. We saw almost the same pattern on our login endpoint last month.
We moved from a scrubbing provider to always-on last year; time to mitigation went from minutes to basically nothing.