A denial of service vulnerability was found in the WhiteHEAT USB Serial Driver (whiteheat_attach function in drivers/usb/serial/whiteheat.c). In the driver, the COMMAND_PORT variable was hard coded and set to 4 (5th element). The driver assumed that the number of ports would always be 5 and used port number 5 as the command port. However, when using a USB device in which the number of ports was set to a number less than 5 (for example, 3), the driver triggered a kernel NULL-pointer dereference. A non-privileged attacker could use this flaw to panic the host.