Where is user as well as admin details such as userid , password are stored?

[Rashi]

Sir can you also tell where are the username and password details of
the users as well as admin is stored?

Thanx

[Ian Moore]

Hi,

It is in the "extra data" section of the VirtualBox config. See vboxmanage setextradata and vboxmanage getextradata. It uses the same mechanism as vboxmanage. In phpvirtualbox, the code is in lib/auth/Builtin.php