Re: nis : how to avoid user1 becoming user2 using local root ?

From: Brian Hatch (bri_at_ifokr.org)
Date: 03/28/04

  • Next message: Daniel Souza: "Re: how to avoid user1 becoming user2 using local root ?"
    Date: Sat, 27 Mar 2004 17:03:24 -0800
    To: Fr?d?ric M?dery <mederyf@LEXUM.UMontreal.CA>
    
    
    

    > All linux servers, all nfs share use the root_squash option.
    > We're using NIS
    > All developpers can become root on their local machines.
    >
    > The prob : if user1 do a `su -` on their station. And then, `su user2`
    > they can become user2.
    >
    > For me it's a huge problem (windows don't have this prob, local admin
    > are very different from domain/server admin) is there a way to avoid
    > this prob ?

    Nope. Not with NFS. NFS uses a 'trust the client' security model.
    If you give users the ability to become root on their machines,
    they can become any user locally, and can access the NFS server as
    that user.

    Later versions of NFS hope to address this problem. Or you can
    try alternate mounting options, such as afs, or even smbmount.

    --
    Brian Hatch                  Lord, save me
       Systems and                from your followers.
       Security Engineer
    http://www.ifokr.org/bri/
    Every message PGP signed
    
    



  • Next message: Daniel Souza: "Re: how to avoid user1 becoming user2 using local root ?"

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