Security Basics: Re: Hidden Ports

[Alejandro Flores <alejandro.flores () triforsec com br>]

        Hello,

        If a backdoor is set to only accept connections from a configured ip
address or network, I guess that nmap will found this port as filtered,
as your ip address is not allowed to connect.

Regards,
Alejandro Flores

> Can a port scanner not see a port that is opened?
>
> The question is: can a backdoor be on a machine, and with nmap -p 1-,
> for example, you couldn't see it?
>
> Thank you,
> Eduardo



--TriForSec
http://www.triforsec.com.br/ 

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