On Tuesday 2 May 2023 at 19:29 UTC, a UDP reflection (DNS) targeted a B2B SaaS customer in North America. The attack peaked at 272.8 Gbps and lasted 126 minutes. Traffic originated from 2485 autonomous systems in 77 countries, predominantly a Mirai-derived IoT botnet.
| Vector | UDP reflection (DNS) |
| Peak | 272.8 Gbps |
| Duration | 126 min |
| Time to mitigation | 0.743 s |
| Attack traffic reaching origin | 0.058% |
| Legitimate traffic challenged | 0.40% |
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 21 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 log streaming to your SIEM for faster correlation.
- Enable authenticated origin pulls.
- Lower challenge thresholds on authentication endpoints during high-risk events.
Thanks — sharing this with our on-call team.