By trying to emulate a real world environment, we have deliberately chosen software solutions, which are ubiquitous in large IT enterprise networks since many years. Many of the examined solutions have a long list of success stories. Quite often these monitoring solutions are the only ones in use in small or mid rage businesses, but surprisingly often enterprise environments use them in a large scale. The wide spread usage of these monitoring solutions is mainly based on the fact that they are free, not expensive to maintain and … secure? We question the last point, while showing how seemingly small security issues may result in large security gaps in your network. Finally we present how compromising one perimetric system may result in a severe security risk for the monitoring network, potentially allowing attacks against further internal networks. This “osmosis” attack clearly shows how the multilayered onion approach can be bypassed by peeling the onion. Finally we will present mitigation proposals to prevent those attacks at least from a design perspective. This talk is for everyone who uses “off the shelf” solutions in sensitive environments, just because everyone else does.