On Friday 25 August 2023 at 05:48 UTC, a search endpoint flood targeted a retail banking customer in Iberia. The attack peaked at 175.9 million requests per second and lasted 187 minutes. Traffic originated from 3529 autonomous systems in 106 countries, predominantly a Mirai-derived IoT botnet.
| Vector | search endpoint flood |
| Peak | 175.9 million requests per second |
| Duration | 187 min |
| Time to mitigation | 0.614 s |
| Attack traffic reaching origin | 0.059% |
| Legitimate traffic challenged | 0.38% |
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 577 within 20 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
- Review allow-listed partner ranges quarterly.
- Enable log streaming to your SIEM for faster correlation.
- Lower challenge thresholds on authentication endpoints during high-risk events.
How do you avoid challenging uptime monitors and partners?
How does the proof-of-work challenge behave on older Android devices? Any numbers below Android 10?
Our auditors asked for exactly this kind of incident evidence under DORA.