On Sunday 16 March 2025 at 19:20 UTC, a GRE flood targeted a online payments customer in North America. The attack peaked at 348.7 Gbps and lasted 162 minutes. Traffic originated from 1931 autonomous systems in 38 countries, predominantly a headless-browser farm.
| Vector | GRE flood |
| Peak | 348.7 Gbps |
| Duration | 162 min |
| Time to mitigation | 0.455 s |
| Attack traffic reaching origin | 0.078% |
| Legitimate traffic challenged | 0.12% |
Timeline
The attack was preceded by an extortion email received two days earlier. 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
No customer-visible impact. The on-call engineer was notified and acknowledged the incident from the dashboard.
Recommendations
- Enable authenticated origin pulls.
- Review allow-listed partner ranges quarterly.
- Add a dedicated rate limit for the targeted route.