Hello,
My host is running Solaris 11.4.81 and I've tried VirtualBox 7.2.4 and 7.2.6. Both have the same issue which makes VirtualBox unusable.
The /opt/VirtualBox/amd64/VirtualBox and /opt/VirtualBox/amd64/VirtualBoxVM processes never exit after powering off the VM and need to be killed manually.
The /opt/VirtualBox/amd64/VBoxHeadless process exits, though.
I have been using VirtualBox 7.1.x for a long time and there is no such problem.
The CPU on the host is Intel Xeon E5-1620 v4.
I performed a test on a different computer with an AMD Ryzen CPU inside a VMware Workstation VM using nested virtualization.
I did a clean installation of Solaris 11.4.81, installed the solaris-desktop package and then installed VirtualBox 7.2.6.
I found exactly the same issue as on my server: VirtualBox and VirtualBoxVM never exit.
The OS on my server is Solaris 11.4 upgraded from 11.3, that's why I decided to test on a clean Solaris 11.4.