XTest is a simple, practical, and free, wired 802.1x supplicant security tool implementing the RFC 3847 EAP-MD5 Authentication method. It can be used to assess the password strength within wired ethernet environments that rely on 802.1x to protect IP Phones and the VoIP Infrastructure against rogue PC access. XTest is developed in C and freely available to anyone, under the GPLv3 license.
XTest was developed with the specific aim of improving the security of environments that use 802.1x to protect IP Phone endpoints and their supporting VoIP Infrastructure. With the increasing prevalence of 802.1x Supplicant support in wired hard Phones, 802.1x will be increasingly used to ensure that remote IP Phones placed in areas with low physical security will have their directly connected ethernet switch ports secured against unauthorized access. Furthermore, the tool can demonstrate the danger [1,2] of relying solely on 802.1x, because the current wired 802.1x implementation only requires authentication when the port initially comes up/up. Subsequent packets are not authenticated, allowing an attacker to share a connection on a hub with the valid 802.1x supplicant, allowing unauthorized switchport access.