Comment # 11 on bug 1222408 from Larry Rainey

The latest 7.0.18 is correct and allows vboxusers to access USB

Is your USB setup in the virtual machine enabled - It has to be to access the
USB.

the output ownership should look like this:

user1@LLR1:~> ll /dev/vb*
crw-rw---- 1 root vboxusers 10, 122 May 21 10:06 /dev/vboxdrv
crw-rw---- 1 root vboxusers 10, 121 May 21 10:06 /dev/vboxdrvu
crw-rw---- 1 root vboxusers 10, 120 May 21 10:06 /dev/vboxnetctl

/dev/vboxusb:
total 0
drwxr-x--- 2 root vboxusers 120 May 22 06:53 001
drwxr-x--- 2 root vboxusers  80 May 21 10:06 002
user1@LLR1:~>