I haven't updated VBOX in ages but have never seen this issue and it has my CPU running at 100C.
Manually/forcefully killing the process does not work with "kill -kill 3892".
I've closed the VBOXManager and everything else related to it.
This did seem to happen around the time I ran VBoxManage clonehd and it failed, the terminal issue locked up and also never wrote a byte of anything. I forced killed the VBoxManage and tried to remove &........
I dread updating the kernel and rebooting to find the Ubuntu graphics aren't working and you have to manually intervene. This is usually because Ubuntu for whatever reason didn't update the drivers you need (eg. the manually compiled Nvidia Kernel driver that MUST be recompiled for each and every kernel update unfortunately).
The most common reason may be that "linux-source" hasn't been installed automatically on my system. I tried to manually reinstall the........