VirtualBox v4.2.12 is released. VirtualBox is a general-purpose full virtualizer for x86/x64 hardware. Targeted at server, desktop and embedded use, it is now the only professional-quality virtualization solution that is also Open Source Software.

VirtualBox v4.2.12 Changelog:
VMM: fixed a Guru Meditation on putting Linux guest CPU online if nested paging is disabled
VMM: invalidate TLB entries even for non-present pages
GUI: Multi-screen support: fixed a crash on visual-mode change
GUI: Multi-screen support: disabled guest-screens should now remain disabled on visual-mode change
GUI: Multi-screen support: handle host/guest screen plugging/unplugging in different visual-modes
GUI: Multi-screen support: seamless mode: fixed a bug when empty seamless screens were represented by fullscreen windows
GUI: Multi-screen support: each machine window in multi-screen configuration should have correct menu-bar now (Mac OS X hosts)
GUI: Multi-screen support: machine window View menu should have correct content in seamless/fullscreen mode now (Mac OS X hosts)
GUI: VM manager: vertical scroll-bars should be now updated on content/window resize
GUI: VM settings: fixed crash on machine state-change event
GUI: don't show warnings about enabled or disabled mouse integration if the VM was restored from a saved state
Virtio-net: properly announce that the guest has to handle partial TCP checksums (bug #9380)
Storage: Fixed incorrect alignment of VDI images causing disk size changes when using snapshots (bug #11597)
Audio: fixed broken ALSA & PulseAudio on some Linux hosts due to invalid symbol resolution (bug #11615)
PS/2 keyboard: re-apply keyboard repeat delay and rate after a VM was restored from a saved state (bug #10933)
BIOS: updated DMI processor information table (type 4): corrected L1 & L2 cache table handles
Timekeeping: fix several issues which can lead to incorrect time, Solaris guests sporadically showed time going briefly back to Jan 1 1970
Main/Metrics: disk metrics are collected properly when software RAID, symbolic links or rootfs are used on Linux hosts
VBoxManage: don't stay paused after a snapshot was created and the VM was running before
VBoxManage: introduced controlvm nicpromisc (bug #11423)
VBoxManage: don't crash on controlvm guestmemoryballoon if the VM isn't running (bug #11639)
VBoxHeadless: don't filter guest property events as this would affect all clients (bug #11644)
Guest control: prevent double CR in the output generated by guest commands and do NLS conversion
Linux hosts / guests: fixed build errors on Linux 3.5 and newer kernels if the CONFIG_UIDGID_STRICT_TYPE_CHECKS config option is enabled (bug #11664)
Linux Additions: handle fall-back to VESA driver on RedHat-based guests if vboxvideo cannot be loaded
Linux Additions: RHEL/OEL/CentOS 6.4 compile fix (bug #11586)
Linux Additions: Debian Linux kernel 3.2.0-4 (3.2.39) compile fix (bug #11634)
Linux Additions: added auto-logon support for Linux guests using LightDM as the display manager
Windows Additions: Support for multimonitor. Dynamic enable/disable of secondary virtual monitors. Support for XPDM/WDDM based guests
X11 Additions: support X.Org Server 1.14 (bug #11609)

Download: VirtualBox v4.2.12
Source: Here