Re: RAZOR advisory: Linux util-linux chfn local root vulnerability

From: Andreas Beck (becka@uni-duesseldorf.de)
Date: Wed Jul 31 2002 - 00:11:20 PDT

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    Andrew Pimlott <andrewat_private> wrote:
    > > > If he is smart, he will check whether the file is open (eg with fuser)
    > > Not really. The file does not have to be open to be present in the system.
    > > It is prefectly possible to leave a dangling root-owned file several
    > > times, 
    > Correct, but: the admin should still verify that it is not open
    > before deleting it (in his cron job).  
    
    As long as there is no atomic "check-if-file-is-open-and-if-not-delete-it"
    this just makes exploitation harder by introducing another race condition.
    
    
    CU, Andy
    
    -- 
    = Andreas Beck                    |  Email :  <beckaat_private>             =
    



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