On Thursday 23 November 2023 at 08:47 UTC, a memcached amplification targeted a electronics retail customer in the UK. The attack peaked at 361.3 Gbps and lasted 142 minutes. Traffic originated from 3279 autonomous systems in 16 countries, predominantly mobile carrier ranges.
| Vector | memcached amplification |
| Peak | 361.3 Gbps |
| Duration | 142 min |
| Time to mitigation | 0.074 s |
| Attack traffic reaching origin | 0.067% |
| Legitimate traffic challenged | 0.79% |
Timeline
The attack was preceded by no stated motive. Edge packet filters identified the flood by source port and payload signature and dropped it at line rate across 18 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
- Lower challenge thresholds on authentication endpoints during high-risk events.
- Enable log streaming to your SIEM for faster correlation.
- Enable authenticated origin pulls.
Could you share the dataset behind the percentages?
Nice to read a vendor blog that admits what went wrong.
Thanks — sharing this with our on-call team.
Thanks — sharing this with our on-call team.
The billing model is what got our finance team on board, honestly.
The point about origin IPs leaking through certificate transparency logs is underrated.