VirtualBox is an application installed on an existing host operating system; within this application, additional operating systems can be loaded and run, each with its own virtual environment. For example, several Linux distributions can be hosted on a single machine running Windows XP; likewise, XP and Vista can run on a machine running Linux, and so on. There is a free for personal or evaluation use proprietary version and a GNU General Public License (GPL) version.
VMM: Fixed a bug while walking page tables while executing nested VMs causing flooding of the release log as a consequence (Intel hosts only, bug #21551)
GUI: Added general improvements
TPM: Fixed a crash when a VM has a TPM version 1.2 configured (bug #21622)
3D: Initial support for OpenGL 4.1
3D: Fixed various graphics issues with Windows 11 guests (bugs #21136, #21515)
Guest Control/VBoxManage: Fixed behavior of how handling argument 0 for a started guest process works: One can now explicitly specify it with the newly added option "--arg0". This will effectively restore the behavior of former VirtualBox versions
Audio: Also use the PulseAudio backend when pipewire-pulse is running instead of falling back to ALSA (bug #21575)
NAT: Adjusted UDP proxy timeout from 18-21 to 21-24 range to respect intended 20 second timeout (bug #21560)
Linux Host: Added initial support for Indirect Branch Tracking (bug #21435)
Linux Host: Added initial support for kernel 6.5 (NOTE: Guest Additions do not support kernel 6.5 yet)
Solaris Host: Introduced general improvements in the installer area
Linux Host and Guest: Improved condition check when kernel modules need to be signed
Linux Host and Guest: Added initial support for RHEL 8.8 (bug #21692), 8.9 (bug #21690) and 9.3 (bugs #21598 and #21671) kernels
MacOS Host and Guest: Introduced general improvements in the installer area
Windows Host and Guest: Introduced ECDSA support (bug #21621)
Linux Guest Additions: Fixed issue when kernel modules were rebuilt on each boot when guest system has no X11 installed
Linux Guest Additions: Added initial support for kernel 6.4
Linux Guest Additions: Fixed issue when vboxvideo module reloading caused kernel panic in some guests (bug #21740)
Linux Guest Additions: Introduced general improvements in the installer area
Windows Guest Additions: Introduced general improvements in graphics drivers area