The create_fixed_stream_quirk function in sound/usb/quirks.c in the snd-usb-audio driver in the Linux kernel before 4.5.1 allows physically proximate attackers to cause a denial of service (NULL pointer dereference or double free, and system crash) via a crafted endpoints value in a USB device descriptor.
The hub_activate function in drivers/usb/core/hub.c in the Linux kernel before 4.3.5 does not properly maintain a hub-interface data structure, which allows physically proximate attackers to cause a denial of service (invalid memory access and system crash) or possibly have unspecified other impact by unplugging a USB hub device.