The last two years have seen a big new marketing-buzz named “Admission Control” or “Endpoint Compliance Enforcement” and most major network and security players have developed a product-suite to secure their share of the cake. While the market is still evolving one framework has been getting a lot of market-attention: “Cisco Network Admission Control”. NAC is a pivotal part of Cisco’s “Self Defending Network” strategy and supported on the complete range of Cisco network- and security-products. From a security point of view “NAC” is a very interesting emerging technology which deservers some scrutiny. The Cisco NAC solution contains two major design-flaws which enable us to hack (at least) two of the three different variants using some kind of “posture spoofing attack”. We will demonstrate code & tool for posture spoofing in Cisco NAC ‘secured’ networks.