On Wednesday 31 January 2024 at 14:21 UTC, a GRE flood targeted a crypto exchange customer in Western Europe. The attack peaked at 74.8 Gbps and lasted 75 minutes. Traffic originated from 2419 autonomous systems in 25 countries, predominantly compromised cloud VMs.
| Vector | GRE flood |
| Peak | 74.8 Gbps |
| Duration | 75 min |
| Time to mitigation | 0.502 s |
| Attack traffic reaching origin | 0.030% |
| Legitimate traffic challenged | 0.37% |
Timeline
The attack was preceded by a hacktivist channel announcing the target. Edge packet filters identified the flood by source port and payload signature and dropped it at line rate across 29 points of presence.
What the customer saw
A brief increase in p99 latency of 48 ms during the first minute, then normal service.
Recommendations
- Add a dedicated rate limit for the targeted route.
- Enable authenticated origin pulls.
- Lower challenge thresholds on authentication endpoints during high-risk events.