VirtualBox fullscreen grabs keyboard, can't type password from locked screen

[Ketil]

I'm running Ubuntu 14.04 64bit (fresh install) with VirtualBox 4.3.10-dfsg-1, and a Windows 7 professional guest (also 64 bit). I have installed the Guest Additions in the guest OS (from the guest additions Ubuntu package, not downloaded by virtualbox).

If I run my guest OS in full screen and Ubuntu locks the screen, I can't log back in again because the keyboard won't type. Searching online I found the same issue reported on the VirtualBox bugtracker:

https://www.virtualbox.org/ticket/13010

After experiencing this 3 times in an hour, I found that hitting Right-Ctrl (which is the host key in virtualbox) releases the keyboard and I can type again, so that seems to be a successful workaround. Mouse events also appear to be captured, so clicking on menu items on the locked screen (as suggested on the link above) doesn't help, although I can move the pointer with the mouse when I see the locked screen.

$ lsb_release -rd:
Description: Ubuntu 14.04 LTS
Release: 14.04

$ apt-cache policy virtualbox
virtualbox:
  Installed: 4.3.10-dfsg-1
  Candidate: 4.3.10-dfsg-1
  Version table:
     4.3.10-dfsg-1 0
        500 http://archive.ubuntu.com/ubuntu/ trusty/multiverse amd64 Packages
        100 /var/lib/dpkg/status

[Ketil (ketil-froyn)]

The same issue is discussed on ubuntuforums here:

http://ubuntuforums.org/showthread.php?t=2220217

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[pobbel (p-burne)]

This also occurs for me using 14.04, and WinXP vbox client.

I resort to Right Ctrl then Ctr+Alt+<arrow> to switch workspace from vbox workspace (this all occurs in the background).
Occasionally I also then need to put the machine into standby using the mouse to access the menu in the top right corner.
The keyboard usually gets focus back when waking from standby.

$ lsb_release -rd:
Description: Ubuntu 14.04 LTS
Release: 14.04

$ apt-cache policy virtualbox
virtualbox:
  Installed: 4.3.10-dfsg-1
  Candidate: 4.3.10-dfsg-1
  Version table:
 *** 4.3.10-dfsg-1 0
        500 http://au.archive.ubuntu.com/ubuntu/ trusty/multiverse i386 Packages
        100 /var/lib/dpkg/status

[pobbel (p-burne)]

Could this be a duplicate of Bug #1305586?

[Ketil (ketil-froyn)]

Could be the same bug, but not necessarily. I guess it depends on whether the modal password prompt and running virtualbox in full screen grabs the keyboard the same way.

In any case, I'd like to make this virtualbox issue a security issue. Users will invariably type their passwords into whatever is active in the virtual machine, which could be google searches, chats, documents, facebook status updates - whatever. That's actually very serious.