On Monday 25 March 2024 at 02:28 UTC, a memcached amplification targeted a online payments customer in the UK. The attack peaked at 80.9 Gbps and lasted 154 minutes. Traffic originated from 2013 autonomous systems in 58 countries, predominantly compromised cloud VMs.
| Vector | memcached amplification |
| Peak | 80.9 Gbps |
| Duration | 154 min |
| Time to mitigation | 0.218 s |
| Attack traffic reaching origin | 0.051% |
| Legitimate traffic challenged | 0.13% |
Timeline
The attack was preceded by a breaking political story. Edge packet filters identified the flood by source port and payload signature and dropped it at line rate across 40 points of presence.
What the customer saw
Checkout conversion was unchanged compared with the same hour of the previous week.
Recommendations
- Review allow-listed partner ranges quarterly.
- Lower challenge thresholds on authentication endpoints during high-risk events.
- Add a dedicated rate limit for the targeted route.