FreeBSD Security Advisory FreeBSD-SA-02:07 - The k5su command included with FreeBSD, versions prior to 4.5-RELEASE, and the su command included in the heimdal port, versions prior to heimdal-0.4e_2, use the getlogin system call in order to determine whether the currently logged-in user is 'root'. In some circumstances, it is possible for a non-privileged process to have 'root' as the login name returned by getlogin. You don't actually want that to happen, trust us.
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