who

[paul () BOEHM ORG (Paul Boehm)]

Hi,
the 'who' program is on some systems in a privileged group
which is allowed to read utmp. On redhat linux 5.1 you can
easily crash who by many different ways (e.g. try who /bin/bash)
on freebsd you can use it to view parts of the content of files that
privileged group may read(try who /privileged/group/file).

this is no big deal with security, but gaining a more privileged group
sometimes may be the key to root compromise.

bye,
    pb

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[ Paul S. Boehm | paul () boehm priv at | http://paul.boehm.org/ | infected@irc ]

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