36 lines
1.3 KiB
Text
36 lines
1.3 KiB
Text
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security,
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Nico Schottelius 2005-06-13 (Last Modified: 2005-06-14)
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A little note about cinit security and how to exploit it:
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cinit trusts its socket, /etc/cinit/tmp/coala. If somebody not
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authorised has access to it, your system is taken over.
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Through this socket anybody with write access can:
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- shutdown, restart and power-off the host
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- spawn a local unprotected shell
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- execute anything as the user cinit runs (most likely root)
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Currently cinit does not care very much about the socket permissions.
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On my system this creates a socket with srwxr-x-rx permissions, which
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isi suitable for normal operation, which will not accept connect()
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by others than root.
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But you can also loosen the security and allow people from a specfic group
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to control your system:
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ei # chmod 770 /etc/cinit/tmp/coala
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ei # chown root:cinit /etc/cinit/tmp/coala
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Now everybody in the cinit group can control your system.
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Please think twice before doing that, as you read above, anyone from
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the cinit group may start a root shell on the initial console then!
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For extra parnoid settings you can do the following:
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ei # chmod 700 /etc/cinit/tmp/coala
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ei # chown root:root /etc/cinit/tmp/coala
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