On Saturday 10 April 2021 at 15:16 UTC, a memcached amplification targeted a healthcare portal customer in Southeast Asia. The attack peaked at 31.7 Gbps and lasted 159 minutes. Traffic originated from 2773 autonomous systems in 51 countries, predominantly compromised cloud VMs.
| Vector | memcached amplification |
| Peak | 31.7 Gbps |
| Duration | 159 min |
| Time to mitigation | 0.575 s |
| Attack traffic reaching origin | 0.003% |
| Legitimate traffic challenged | 0.61% |
Timeline
The attack was preceded by a ransom note demanding payment in Monero. Edge packet filters identified the flood by source port and payload signature and dropped it at line rate across 31 points of presence.
What the customer saw
The customer’s status page stayed green throughout; they learned about the attack from our notification.
Recommendations
- Enable authenticated origin pulls.
- Keep origin IPs out of public DNS history.
- Lower challenge thresholds on authentication endpoints during high-risk events.