is this a legitimate cron job? Maybe you might inspect it? At least from my perspective it looks a bit strange. So maybe sb broke in your server, so you should check what kind of applications / script are running for web2.
You might also check rkhunter (rootkit.nl).
Regarding running a cronjob every five minutes, set the minute portion to */5 everything else to *
e.g. */5 * * * * <command>
you should also consider using logwatch, as it would email you such kind of stuff on a daily basis.