Fortinet Discovers Citrix XenCenter DLL Preloading Vulnerability
Fortinet's FortiGuard Labs has discovered a DLL preloading vulnerability in Citrix's XenCenter.
XenCenter is the management UI for XenServer virtual environments. Using XenCenter, all virtual machines of a running host can be managed in a convenient way. In addition to the creation of virtual machines, XenCenter provides more possibilities for the administration of a Xen host including the creation of snapshots of the virtual machines as well as adding and manipulating the storage repositories that serve as memory for the virtual machines.
XenCenter for Windows is susceptible to a DLL preloading vulnerability. The issue occurs when the application looks to load a DLL for execution and an attacker provides a malicious DLL to use instead. The application generally follows a specific search path to locate the DLL. The vulnerability can be exploited by a simple file write (or potentially an over-write) which results in a foreign DLL running under the context of the application.
Users should apply the solution provided by Citrix Systems.
Fortinet reported the vulnerability to Citrix Systems on June 4, 2017.
Citrix Systems confirmed the vulnerability on July 28, 2017.
Citrix Systems patched the vulnerability on November 23, 2017.