can i use virtualbox to test malware?

[EtherealWorksFin1]

or will it affect the main operating system?

i want, for example, download virus and check out what happens to windows. i use kaspersky internet security - virtualbox has all rights allowed. is this dangerous then?

the other hand is that i have a shared folder, which is excluded from kaspersky scanner.

[vbox4me2]

If it runs you can use it, don't ask for further details here, join a dedicated AV forum for that purpose.