Either lower the number of vCPUs to 1 or upgrade to BigSur or later where the issue does not occur

Known issue: VMs having more than one vCPU configured will not work properly on macOS Catalina due to an unknown memory corruption issue.

The following items were fixed and/or added:

Like many other virtualization solutions, for easy data exchange between hosts and guests, VirtualBox allows for declaring certain host directories as 'shared folders', which can then be accessed from within virtual machines. There are also guest additions for OS/2 with somewhat reduced functionality. Among the features provided by these Guest Additions are mouse pointer integration and arbitrary screen solutions (e.g. VirtualBox has special software that can be installed inside Windows, Linux and Solaris virtual machines to improve performance and make integration much more seamless.

Guest Additions for Windows, Linux and Solaris. Virtual machine definitions can therefore easily be ported to other computers. The configuration settings of virtual machines are stored entirely in XML and are independent of the local machines. VirtualBox also comes with a full Software Development Kit: even though it is Open Source Software, you don't have to hack the source to write a new interface for VirtualBox. This makes it easy to control it from several interfaces at once: for example, you can start a virtual machine in a typical virtual machine GUI and then control that machine from the command line, or possibly remotely. VirtualBox has an extremely modular design with well-defined internal programming interfaces and a client/server design. Targeted at server, desktop and embedded use, it is now the only professional-quality virtualization solution that is also Open Source Software. VirtualBox is a general-purpose full virtualizer for x86 hardware.

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