Re: smbd remote file creation vulnerability

From: Simple Nomad (thegnomeat_private)
Date: Tue Jun 26 2001 - 13:46:01 PDT

  • Next message: Wichert Akkerman: "Re: smbd remote file creation vulnerability"

    The limit on the netbios name length must include the ../../../ as a part
    of the name, so you've blown 9 characters right there to get to the root
    dir. Otherwise you could get to /etc/crontab or something and the exploit
    would not require a symlink. So the file can be created remotely, but as
    for the symlink that requires local access.
    
    Of course you could try to point /tmp/x.log to ~personaldir/tmp/x.log
    which points to /etc/passwd, but that still won't work under the Openwall
    patch (just checked to make sure).
    
    -         Simple Nomad          -     "No rest for the Wicca'd"     -
    -      thegnomeat_private        -                                   -
    -  thegnomeat_private  - www.nmrc.org   razor.bindview.com -
    
    
    On Tue, 26 Jun 2001, Pavol Luptak wrote:
    
    > On Tue, Jun 26, 2001 at 09:53:29AM +0300, Jarno Huuskonen wrote:
    > > On Mon, Jun 25, Pavol Luptak wrote:
    > > > Linux kernels with openwall patch (with restricted links in /tmp) are
    > > > imunne to this type of attack (following symlinks does not work, link
    > > > owner does not match with file's owner).
    > >
    > > The symlink restrictions work only in /tmp (mode 1777) directories, so
    > > making the symlink in your own homedir still works (should work).
    >
    > Yes, the symlink does not have to be in /tmp, but you have to ensure
    > the path to your symlink in your own homedir is enough short to fill in
    > NetBIOS name (about 15 characters).
    > --
    > _______________________________________________________________________
    > [wilderat_private] [http://hq.alert.sk/~wilder] [talker: ttt.sk 5678]
    >
    



    This archive was generated by hypermail 2b30 : Wed Jun 27 2001 - 15:02:25 PDT