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security,
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:

cinit trusts its socket, /etc/cinit/tmp/coala. If somebody not
authorised has access to it, your system is taken over.

Through this socket anybody with write access can:

   - shutdown, restart and power-off the host
   - spawn a local unprotected shell
   - execute anything as the user cinit runs (most likely root)

Currently cinit does not care very much about the socket permissions.
On my system this creates a socket with srwxr-x-rx permissions, which
isi suitable for normal operation, which will not accept connect()
by others than root.

But you can also loosen the security and allow people from a specfic group
to control your system:

   ei # chmod 770 /etc/cinit/tmp/coala
   ei # chown root:cinit /etc/cinit/tmp/coala

Now everybody in the cinit group can control your system.
Please think twice before doing that, as you read above, anyone from
the cinit group may start a root shell on the initial console then!

For extra parnoid settings you can do the following:

   ei # chmod 700 /etc/cinit/tmp/coala
   ei # chown root:root /etc/cinit/tmp/coala