.TH CRON.CHK 1 "December 31, 1989"
.UC 4
.SH NAME
cron.chk  \- Checks contents of cron file(s) for potential danger.
.SH SYNOPSIS
.B cron.chk
.SH DESCRIPTION
.I cron.chk
checks pathnames and files inside the cron files for writability.
It filters out all paths or files that have a /tmp, /dev/null,
or /dev/*ty, plus everything after a ">"; e.g. if crontab is writing
to a file it doesn't care.
.PP
Since cron is run with root privileges, any file that root uses as input
inside the cron files or any program that root executes is potential danger.
World writable files can be changed by anyone to cause a root owned process
to give away unwarranted privileges.
.SH FILES
/usr/lib/cron
/usr/spool/cron/crontabs/*
.SH "SEE ALSO"
is_able(1)
.SH BUGS
Spurious messages can occur; a more stringent method (if perhaps less
careful of a check) would be to test just the 6th field, instead of
all the fields after the fifth.  Also throwing away /tmp, etc. could
be a mistake.
