memory – Can VirtualBox .sav files expose sensitive data (RAM contents) and how to extract them?

I have a .sav file created by VirtualBox when a VM was suspended. The VM handles secure keys, and I’m concerned that the .sav file may contain sensitive data.

From my understanding, .sav files can store the VM’s RAM contents at the moment of suspension. By inspecting the file in a hex editor, I’ve already found readable labels like “Memory Manager” in certain sections, which suggests that parts of the guest memory are indeed present.

I want to know:

Does a .sav file store the full RAM contents of the VM or only partial state?

Is there an easier or more structured way to extract or search for specific memory contents (like my predefined keys) from the .sav file without running the VM again?

What tools or methods could I use to parse and analyze the .sav format for this purpose?

My goal is to determine whether keeping .sav files on an unprotected device poses a security risk.