VirtualBox v5.1.20 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 v5.1.20 Changelog:
* GUI: don't check if the Extension Pack is up-to-date if the user is about to install a new Extension Pack (bug #16317)
* GUI: fixed a possible crash when switching a multi-monitor VM into full-screen or seamless mode
* GUI: fixed non-literal shortcuts if the keyboard is not captured (5.1.10 regression; Windows hosts only)
* GUI: several mini-toolbar fixes in full-screen / seamless mode (X11 hosts only)
* GUI: don't crash on restoring defaults in the appliance import dialog
* Windows Additions: another fix for automatic logins for Windows Vista and newer (bug #15904)
* ICH9: fix for Windows guests with a huge amount (>64G) of guest memory
* BIOS: fixed El Torito hard disk emulation geometry calculation (thanks Dwight Engen)

Download: VirtualBox v5.1.20
Source: Here