According to a number of Linux distributors, a bug in the udev service under Linux can be exploited to obtain root privileges. The kernel uses udev to dynamically create device-specific files and folders (/dev/) for input and output, so that only devices which are actually connected appear in /dev. udev is not a direct component of the Linux kernel, but is included and activated by default in almost all Linux distributions which use 2.6 series kernels.