Piracy: ꜱᴀɪʟ ᴛʜᴇ ʜɪɢʜ ꜱᴇᴀꜱ

The point is that you isolate the VM after you get the file onto it but before running the potential malware. It's not going to auto-execute, not if your Windows is patched and modern and up to date, we don't live in the bad old days of floppy disks and CDs and USBs autorunning anymore (and for good reason).

If you are running a version of Windows (or anything) that is even capable of auto-executing code as it downloads, the malware you're trying to test is the least of your worries because you'll already have about a thousand other malware already running.

Create an ISO and mount that.

But really, it doesn't matter how you get the file in before you open it. It's extremely unlikely that it malware could be executed just by putting a file on disk.

Based on our recent interactions, I would say you probably don't have the expertise necessary to evaluate whether the file's safe. I very much doubt you're gonna gain any new knowledge from doing this.

This isn't a slight against you. I don't have the expertise, either.

encode it in base 64 and type it in

Start off with a clean slate. Windows, freshly installed from a Microsoft provided ISO (Assuming you're looking at a Windows executable). Try to follow a guide on bypassing the MS account requirement (AtlasOS has a section of their guide telling you how to do this).

When you're setting things up, there's no restrictions to internet access, sharing, etc. You just have to be careful not to open/view the files you want to isolate, which is easy enough by for example putting the files in a password protected zip. You can also install any required tools now (like maybe 7zip).

At this stage, there's a few options:

• The easiest is to put your files into a separate folder, then run a simple webserver, like with python3 -m http.server on your host. Then download it on the VM.
• Another option is to mount the VMs disk, then copy the files directly. Turn off the VM, mount the disk, copy the files, unmount, then turn it back on.
• You could create a disk image that contains your files, readable by the VM.

When you're ready to actually open the file, close off all access from the VM to the host. No networking, clipboard sharing, etc. Do this on the hosts VM settings, not inside the VM. Also note that without further tooling, it's extemely difficult to tell if there's any advanced malware present.

As soon as you view the potentially malicious files, consider anything coming from that VM as malicious. Don't try to view/open files on your host, do not give it network access.

Malware can be (but often isn't) incredibly advanced, and even an isolated VM isn't a 100% guaranteed method of keeping it contained.

Personally I just copy/paste into the VM over a network share, then disable networking before running (or enable with a firewall rule on the hypervisor to allow only internet access for the VM if it needs it)