Re: ICMP (Ping)

[Ansgar Wiechers <bugtraq () planetcobalt net>]

On 2003-09-02 freeasabird_13 () gmx net wrote:
> > Are there any security issues for allowing a firewall/router to
> > respond to Ping from the internet?
>
> Yes.  It would not be preferable for you to allow your firewall/router
> to respond to pings from the internet.  Someone running a wide-scale
> scan of internet computers for possible attack targets would quickly
> be made aware of your obvious internet presence and you could become a
> target for attack.

I don't think so. Not responding to ICMP echo-requests won't make you
invisible. Whenever a ping does not return "host unreachable" you know
there *is* something with that address.
Dropping ICMP packets might be useful though, to protect the firewall
or router from being DoS'ed through ICMP, but it won't hide your host.

Regards
Ansgar Wiechers

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