The clie_5_attach function in drivers/usb/serial/visor.c in the Linux kernel through 4.4.1 allows physically proximate attackers to cause a denial of service (NULL pointer dereference and system crash) or possibly have unspecified other impact by inserting a USB device that lacks a bulk-out endpoint. http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2015-7566
