https://poppopretn.com/2020/11/06/sans-infosec-handlers-diary-blog-rediscovering-limitations-of-stateful-firewalls-nat-slipstreaming-implications-detections-and-mitigations/
SANS InfoSec Handlers Diary Blog - Rediscovering Limitations of Stateful Firewalls: "NAT Slipstreaming" ? Implications, Detections and Mitigations