vrdp authentication (External) for multiple users fail

[Perry G]

In previous version it has been able for different users to authenticate (external) as long as they had valid accounts on the Host system. Now it appears that this does not work. Has something changed that does not allow this now? I have read the Users manual and it still states that anyone that has an account on the host would be authenticated, but this just is not the case now.

I have tried this on both Windows host and Linux host and while I am able to authenticate if I use the login that started the host it works, but if I use a different login (as is the case with multiple sys admins) it reports back a failure.

The failure error is: perry-laptop unix_chkpwd[7504]: password check failed for user (bob) Dec 9 12:49:02 perry-laptop VirtualBox: pam_unix(login:auth): authentication failure; logname= uid=1000 euid=1000 tty= ruser= rhost= user=bob

The uuid and euid are the ones for the user that started the host and the guest which do not represent the actual uuid and euid of the person logging in (1002)

I have also validated that both users are in the shadow file and even used the broken_shadow statement but the outcome does not change.

Log file showing both logins attached and One success and one failed. Please let me know if you need more information.

[Perry G]

Logfile of failure to authenticate (external)

[Klaus Espenlaub]

I see the same behavior, however the VirtualBox PAM auth module doesn't perform any user name checks, it just passes whatever it got from RDP to PAM. Seems there is a check somewhere outside our control which limit regular users to verify only their own password.

[Perry G]

Thanks klaus,

I felt that I was starting to loose it. So somewhere inside the host they are pressing the uuid/euid issue I assume. I say this because the guest that is logging in simply provides the name and password and it is authenticating against the person that started the session. Since the name and password does not match the uuid/euid it is denied.

You can mark this ticket as closed as it now is up to me to find out what needs to be changed in the PAM of the host to allow different users login permission.

Much appreciated.

[Jacek Bilski]

Is there something going on with this issue? I have a problem with this issue, because I need to let multiple user to work on one virtual machine using VRDP. Or maybe there is some workaround?

[Patrik Dufresne]

+1 here

Using VirtualBox 4.0.10 on Ubuntu 10.04.2 LTS 64bits has the same behavior. Only the vm's owner may login to VRDP when using external authentication module.

[Malden]

Hit the same problem with Virtualbox 4.1.12 on Ubuntu 12.04. This is quite a serious limitation. Can someone please provide a workaround, as it seems that this is not going to be fixed any time soon.

Thanks

[Frank Mehnert]

Please reopen if still relevant with VBox 5.0.14.