iago-vL writes "Security researchers at SkullSecurity have demonstrated how the NetBIOS protocol allows trivial hijacking due to its design, through the use of a tool called 'nbpoison' (in the package 'nbtool'). If a DNS lookup fails on Windows, the operating system will broadcast a NetBIOS lookup request that anybody can respond to. One vector of attack is against business workstations on an untrusted network, like a hotel; all DNS requests for internal resources can be redirected (Exchange, proxy, WPAD, etc). Other attack vectors are discussed in a related blog post. Although similar attacks exist against DHCP, ARP and many other LAN-based protocols, we all know that untrusted systems on a LAN means game over. NetBIOS poisoning is much quieter and less likely to break other things."