Why Does Your Origin Still Get Overwhelmed After Using a High-Defense CDN? Uncovering Origin IP Leak Paths and Building an Anti-Bypass Back-to-Origin

Amid the normalization of high-frequency short-duration DDoS attacks in 2026, this article systematically dissects the two types of defense failures—direct origin bypass and back-to-origin penetration—that cause origin servers to remain saturated or blackholed even after deploying a high-defense CDN. It outlines six major origin IP leakage paths and provides a complete anti-bypass solution: seamless CNAME integration, IP replacement and whitelisting, and back-to-origin access control.