2 problems with CIS v4

Comodo Internet Security - CIS Firewall Help - CIS
1

Have been using CIS for years and have the very latest v4 CIS working under Windows XP SP3.

First problem:
Using shields up to test for stealth on the common ports, sadly port 0 is shown as being “closed”. Is this a bug?

Second problem:
Stealth Ports Wizard always defaults to "“Define a new trusted network …” even if you select “Block all incoming connections …”. Is this also a bug?

Thanks, John

2

  1. Quote from grc : ““Port Zero” does not officially exist. It is defined as an invalid port number. But valid Internet packets can be formed and sent “over the wire” to and from “port 0” just as with any other ports.”
    and other : “Port 0 is officially a reserved port in TCP/IP networking, meaning that it should not be used for any TCP or UDP network communications.”
    So although you can force packets to that port number it isn’t used by any application.
    Also, when running shields up or similar tests make sure you aren’t behind a router, modem, etc. and that it your machine that’s being tested and not the hardware firewall on the router.

  2. Stealth ports wizard will always look like that when you run it. It’s a wizard, not an options screen. All settings applied through it can be viewed under firewall global rules.

3

[quote author=cristi_np link=topic=54158.msg382446#msg382446 date=1269525616]

  1. Quote from grc : ““Port Zero” does not officially exist. It is defined as an invalid port number. But valid Internet packets can be formed and sent “over the wire” to and from “port 0” just as with any other ports.”
    and other : “Port 0 is officially a reserved port in TCP/IP networking, meaning that it should not be used for any TCP or UDP network communications.”
    So although you can force packets to that port number it isn’t used by any application.
    Also, when running shields up or similar tests make sure you aren’t behind a router, modem, etc. and that it your machine that’s being tested and not the hardware firewall on the router.

I understand your point regarding port 0, but in the former days of CIS v3 and using GRC for testing for stealth capabilities I found that all the ports were stealthed. But ever since using CIS v4 using the same test for stealth capabilities, port 0 is identified as being closed. How can CIS v3 and v4 be the same if they produce a different result in GRC shields up? I wont ever stop using v4 as I am a fan of CIS and of v4, it’s just that it simply mystifies me as to why port 0 is closed in v4 when it was formally stealthed in v3 of CIS