Re: Irix tape devices + logs + su

From: Valdis.Kletnieksat_private
Date: Fri Dec 18 1998 - 15:05:58 PST

  • Next message: Kevin K. Sochacki: "DoS caused by lpd"

    --==_Exmh_522684854P
    Content-Type: text/plain; charset=us-ascii
    
    On Thu, 17 Dec 1998 09:39:11 +0200, you said:
    > entry in root's .cshrc)). So it is possible to have those devices with
    > mode 644 or even 666, which is bad news, because anyone could use
    > xfsrestore to get any file.
    
    Possibly an issue.  Remember that they still need physical access to
    the tape and the tape drive.  xfsrestore isn't set-UID, so a user
    can't extract files with a different owner unless they get root first.
    
    I'd worry more about someobdy doing an 'mt rewindoffline' to screw up
    a running tape job.
    
    >  Also, /var/adm/SYSLOG contains the failed login names (even if they
    > don't exist) and by default, this file is forced to be mode 644 (root's
    > crontab will take care for this, when rotating the logs).
    
    This can be an issue.
    
    >  Finaly, when using su, the user's .cshrc will be executed with
    > privileges of the target user (if the su is succesful). For example,
    > if user nobody has a cp /bin/sh /tmp; chmod 6755 /tmp/sh in his .cshrc
    > and he use su to become root, a rootshell will be available in /tmp :)
    > This is valid only for succesfull su's
    
    So?  They're root, and they could do that *anyhow*. No exposure here.
    
    Now, if the user can trick the sysadmin into su'ing and running the
    user's .cshrc *instead* of the sysadmin's, that's more interesting. ;)
    
    --
                                    Valdis Kletnieks
                                    Computer Systems Senior Engineer
                                    Virginia Tech
    
    
    --==_Exmh_522684854P
    Content-Type: application/pgp-signature
    
    -----BEGIN PGP MESSAGE-----
    Version: 2.6.2
    
    iQCVAwUBNnrf1dQBOOoptg9JAQET+QP+KtVN9IGlYtpq6OqI3QXXvKfIa2NdHhbY
    WUnDWTUibhPlguxv1hIIaMtgxSmy6nKkLEqXdGMC4S2mwZRQLeiuZbuPgySzsjBO
    UOjAc4h8Xaod5R8Te9als/MTxMoBRQSJzWclj6658371Cm5HXd2sE33hmmuN982U
    i2t1Mx+Ko0g=
    =/j5Z
    -----END PGP MESSAGE-----
    
    --==_Exmh_522684854P--
    



    This archive was generated by hypermail 2b30 : Fri Apr 13 2001 - 14:25:12 PDT