/usr/share/syslinux/themes/ubuntu-wily/isolinux-live/isolinux.bin is in syslinux-themes-ubuntu-wily 12.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/syslinux/themes/ubuntu-wily/isolinux-live/../../../../../lib/ISOLINUX/isolinux.bin