Re: Attacks on unreachable systems

["Perry E. Metzger" <pmetzger @ lehman . com>]

Tom Fitzgerald says:
> An intruder who
> reached a system inside a firewall, just once, could install a cron job
> that, at a particular time every night, initiated a telnet connection to a
> high-numbered port on an outside site, and exec'd a shell if the connection
> succeeded.

If the routers on the your DMZ won't let through arbitrary TCP
connections going out, you are safe from this.

Perry