On Sunday 15 May 2022 at 12:42 UTC, a ACK flood targeted a news publisher customer in Southeast Asia. The attack peaked at 247.8 Gbps and lasted 4 minutes. Traffic originated from 2945 autonomous systems in 77 countries, predominantly compromised cloud VMs.
| Vector | ACK flood |
| Peak | 247.8 Gbps |
| Duration | 4 min |
| Time to mitigation | 0.256 s |
| Attack traffic reaching origin | 0.034% |
| Legitimate traffic challenged | 0.44% |
Timeline
The attack was preceded by a competitor’s product launch. Edge packet filters identified the flood by source port and payload signature and dropped it at line rate across 12 points of presence.
What the customer saw
Checkout conversion was unchanged compared with the same hour of the previous week.
Recommendations
- Lower challenge thresholds on authentication endpoints during high-risk events.
- Enable log streaming to your SIEM for faster correlation.
- Add a dedicated rate limit for the targeted route.