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    2.1 Failing the GRC firewall test

    Scheduled Pinned Locked Moved General pfSense Questions
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    • johnpozJ
      johnpoz LAYER 8 Global Moderator
      last edited by

      Dude I don't know what your scanning but it sure is not pfsense..  I assure you pfsense default rules would be completely stealth… Here is scan of my 2.1 box

      GRC Port Authority Report created on UTC: 2013-11-21 at 22:31:00

      Results from scan of ports: 0-1055

      1 Ports Open
          0 Ports Closed
      1055 Ports Stealth

      1056 Ports Tested

      NO PORTS were found to be CLOSED.

      The port found to be OPEN was: 443

      Other than what is listed above, all ports are STEALTH.

      TruStealth: FAILED - NOT all tested ports were STEALTH,
                        - NO unsolicited packets were received,
                        - A PING REPLY (ICMP Echo) WAS RECEIVED.

      443 is port I have open for openvpn tcp.. So I can get there from where ever, etc.  And yes I allow pings - here are my firewall wan rules - see attached

      Not sure what your scanning - but lets say pfsense firewall was down.. Look at what pfsense is running, its NOT listing on those ports you say are are open..  Look at what your pfsense is listening on

      sockstat -4 -l
      See 2nd pick of mine..  If pfsense is not listening on those ports you show open, how would they be open??  What does your sockstat look like?

      So how would they show open??  You sure you don't have some 1:1 nat setup scanning something inside your network.  Or scanning something in front of pfsense?

      wanrules.png
      wanrules.png_thumb
      sockstat.png
      sockstat.png_thumb

      An intelligent man is sometimes forced to be drunk to spend time with his fools
      If you get confused: Listen to the Music Play
      Please don't Chat/PM me for help, unless mod related
      SG-4860 24.11 | Lab VMs 2.8, 24.11

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      • N
        Nachtfalke
        last edited by

        My pfsense only shows the open port 443 TCP for my VPN, too. All other ports are stealth.
        And even if I do not allow ping on my pfsense WAN site the website shows it allows pings. This is probably because I have some other routers/modems in front of pfsense which do the dial-up to my ISP.

        So you should check your upstream routers/modems if the have open ports which could cause that behaviour.

        Further I am not sure if these tests are really good because you open a connection from inside your network to start the test. Probably best test would be to run a NMAP port scan from somewhere else outside your LAN on your WAN IP.

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        • O
          oj88
          last edited by

          Just stating a possibility… Does your pfSense box gets assigned an actual public Internet address? Otherwise, it may just be sitting behind another router doing NAT and what you're seeing are actually GRC results acted on that upstream router and not on the pfSense box.

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          • F
            firewalluser
            last edited by

            The router (British Telecom supplied) is in DMZ mode so I wouldnt have expected that to have been been causing a problem, especially not from a global company like BT, but GRC scanning the router instead of pfsense did cross my mind as suggested above.

            I have a couple more routers here I can try, so will try that. The weird thing I noticed is the pattern of open & stealth ports changes which suggests the router might be getting in the way, because looking in the system log I can see all the packets coming through and being blocked yet GRC was reporting otherwise….

            Maybe this Router is supposed to have some sort of psuedo smart filtering built into it which we dont know about. Certainly with all the stuff they have built with GCHQ/NSA who knows what "extras" the router comes with.

            Capitalism, currently The World's best Entertainment Control System and YOU cant buy it! But you can buy this, or some of this or some of these

            Asch Conformity, mainly the blind leading the blind.

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            • johnpozJ
              johnpoz LAYER 8 Global Moderator
              last edited by

              Great question - when you look at pfsense status, what is its wan address - is it rfc1918??  Or actual public

              Does it start with 10.x.x.x, 192.168.x.x, 172.16-31.x.x??

              You state " in DMZ mode "  That sounds like NAT to me..  So your pfsense is behind a NAT, and your scanning your router in front of it, etc..  What is the IP address of your wan on pfsense?

              Also look at pfsense via sockstat for your own piece of mind – is anything listening on those ports?  If not then how could it show open?  Those ports are under 1024 -- so they sure are not being used as ports to listen for return traffic from your nat clients behind pfsense, etc.

              An intelligent man is sometimes forced to be drunk to spend time with his fools
              If you get confused: Listen to the Music Play
              Please don't Chat/PM me for help, unless mod related
              SG-4860 24.11 | Lab VMs 2.8, 24.11

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              • stephenw10S
                stephenw10 Netgate Administrator
                last edited by

                Which BT router do you have? HomeHub 3? Are you on adsl or fttc?

                Steve

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                • C
                  Chucko
                  last edited by

                  All 1056 ports turned up stealthed in my case. I don't yet have any services enabled through the firewall. The test reported "FAILED" only because I chose to configure pfSense to respond to ICMP Echo (ping).

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                  • T
                    Texnet
                    last edited by

                    Hi Everyone,

                    I know this post is old but i have just installed pfsense for the first time and I am also getting alot of ports open with the default install.  I have opened just 3 ports port 80 for our web server 443 for OWA and 25 for SMTP but I am also getting alot of other ports open according to GRC firewall test.

                    GRC Port Authority Report created on UTC: 2014-10-20 at 11:02:17

                    Results from scan of ports: 0-1055

                    627 Ports Open
                        0 Ports Closed
                      429 Ports Stealth
                    –-------------------
                    1056 Ports Tested

                    NO PORTS were found to be CLOSED.

                    Ports found to be STEALTH were: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
                                                    10, 11, 12, 13, 14, 15, 16,
                                                    17, 18, 19, 20, 21, 22, 23,
                                                    24, 26, 27, 28, 29, 30, 31,
                                                    32, 33, 34, 35, 36, 37, 38,
                                                    39, 40, 41, 42, 43, 44, 45,
                                                    46, 47, 48, 49, 50, 51, 52,
                                                    53, 54, 55, 56, 57, 58, 59,
                                                    60, 61, 62, 63, 64, 94, 128,
                                                    129, 130, 131, 132, 133, 134,
                                                    135, 136, 137, 138, 139, 140,
                                                    141, 142, 143, 144, 145, 146,
                                                    147, 148, 149, 150, 151, 152,
                                                    153, 154, 155, 156, 157, 160,
                                                    161, 162, 163, 164, 165, 166,
                                                    167, 168, 169, 170, 171, 172,
                                                    173, 174, 175, 176, 177, 178,
                                                    179, 180, 181, 182, 183, 184,
                                                    185, 186, 187, 188, 189, 190,
                                                    191, 192, 193, 194, 195, 196,
                                                    197, 198, 199, 200, 201, 202,
                                                    203, 204, 205, 206, 207, 208,
                                                    209, 210, 211, 212, 213, 214,
                                                    215, 216, 217, 218, 219, 220,
                                                    221, 222, 223, 320, 321, 322,
                                                    323, 339, 352, 353, 354, 355,
                                                    356, 357, 358, 359, 360, 361,
                                                    362, 363, 364, 365, 366, 367,
                                                    368, 369, 370, 371, 372, 373,
                                                    374, 375, 376, 377, 378, 379,
                                                    380, 381, 382, 383, 384, 385,
                                                    386, 387, 388, 389, 390, 391,
                                                    392, 393, 394, 395, 396, 397,
                                                    398, 399, 400, 401, 402, 403,
                                                    404, 405, 406, 407, 408, 409,
                                                    410, 411, 412, 413, 414, 415,
                                                    558, 559, 560, 561, 562, 563,
                                                    564, 565, 566, 567, 568, 569,
                                                    570, 571, 572, 573, 574, 575,
                                                    576, 577, 578, 579, 580, 581,
                                                    582, 583, 584, 585, 586, 587,
                                                    588, 589, 590, 591, 592, 593,
                                                    594, 595, 596, 597, 598, 599,
                                                    600, 601, 602, 603, 604, 605,
                                                    606, 607, 608, 609, 610, 611,
                                                    612, 613, 614, 615, 616, 617,
                                                    618, 619, 620, 621, 622, 623,
                                                    624, 625, 626, 627, 628, 629,
                                                    630, 631, 632, 633, 634, 635,
                                                    636, 637, 638, 639, 774, 775,
                                                    800, 801, 802, 803, 804, 805,
                                                    806, 807, 808, 809, 810, 811,
                                                    812, 813, 814, 815, 816, 817,
                                                    818, 819, 820, 821, 822, 823,
                                                    824, 825, 826, 827, 828, 829,
                                                    830, 831, 832, 833, 834, 835,
                                                    836, 837, 838, 839, 840, 841,
                                                    842, 843, 844, 845, 846, 847,
                                                    848, 849, 850, 851, 852, 853,
                                                    854, 855, 856, 857, 858, 859,
                                                    860, 861, 862, 863, 992, 993,
                                                    994, 995, 996, 997, 998, 999,
                                                    1000, 1001, 1002, 1003, 1004,
                                                    1005, 1006, 1007, 1008, 1009,
                                                    1010, 1011, 1012, 1024, 1025,
                                                    1026, 1027, 1028, 1029, 1030,
                                                    1031, 1032, 1033, 1034, 1035,
                                                    1036, 1037, 1038, 1039, 1040,
                                                    1041, 1042, 1043, 1044, 1045,
                                                    1046, 1047, 1048, 1049, 1050,
                                                    1051, 1052, 1053, 1054, 1055

                    Other than what is listed above, all ports are OPEN.

                    TruStealth: FAILED - NOT all tested ports were STEALTH,
                                      - NO unsolicited packets were received,
                                      - NO Ping reply (ICMP Echo) was received.

                    I am using a public IP address on pfsense so shouldn't be seeing the router and the router in also not in DMZ mode.  Anyone have any ideas?

                    Thanks

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                    • johnpozJ
                      johnpoz LAYER 8 Global Moderator
                      last edited by

                      Here is the thing.. Are you forwarding to something?  How is that pfsense would be listening on all those ports "OPEN"

                      Lets think about it for 2 seconds..  For a port to show open something had to reply..  Do you think pfsense replied because it has a service running on say 1042?  What would that service be??  Do a netstat on pfsense to see what is listening..  Did you create any forwards to another that could be listening on those ports?

                      Why don't you do a sniff on your wan when you run this scan..  Diag, packet capture - do you see inbound to those odd ball ports.  You see a syn ack back?  What is in your state table for those ports?

                      An intelligent man is sometimes forced to be drunk to spend time with his fools
                      If you get confused: Listen to the Music Play
                      Please don't Chat/PM me for help, unless mod related
                      SG-4860 24.11 | Lab VMs 2.8, 24.11

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                      • M
                        mikeisfly
                        last edited by

                        Also do you have uPNP enabled? If so that could be a source of your trouble. Check to see which devices are using uPNP and which ports do that have opened.

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                        • K
                          kejianshi
                          last edited by

                          My thoughts exactly.  uPNP may be forwarding  (opening) ports you have not thought about.

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                          • johnpozJ
                            johnpoz LAYER 8 Global Moderator
                            last edited by

                            Concur its quite possible UPnP could open up stuff - clearly this is what is wrong with UPnP in the first place - what would be requesting those privileged ports??

                            An intelligent man is sometimes forced to be drunk to spend time with his fools
                            If you get confused: Listen to the Music Play
                            Please don't Chat/PM me for help, unless mod related
                            SG-4860 24.11 | Lab VMs 2.8, 24.11

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                            • stephenw10S
                              stephenw10 Netgate Administrator
                              last edited by

                              @johnpoz:

                              what would be requesting those privileged ports??

                              A virus? I can't think what else could possibly need 627 ports.
                              UPnP isn't enabled by default though, at least you have to be vaguely aware of the consequences before enabling it. UPnP seems to cover a lot these days though. Although pfSense only implements the port forwarding parts of it I get the impression a lot of people enable it thinking it will help them with DLNA device discovery. It won't.

                              Steve

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                              • johnpozJ
                                johnpoz LAYER 8 Global Moderator
                                last edited by

                                Even a virus would not need 627 ports ;)  While not saying its not UPnP, I would look to something a bit more general in nature like device in front of pfsense.. ISP doing something?  Just plain something broke in GRC?.  Have you tried another scanner? Seem unlikely even that a virus would open 627 ports if you ask me..

                                A 10 second sniff on your wan port would tell you if this traffic is even getting to pfsense and if pfsense or something behind it is answering, etc.

                                An intelligent man is sometimes forced to be drunk to spend time with his fools
                                If you get confused: Listen to the Music Play
                                Please don't Chat/PM me for help, unless mod related
                                SG-4860 24.11 | Lab VMs 2.8, 24.11

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                                • H
                                  Harvy66
                                  last edited by

                                  I've had odd  results with the GRC scan. I'm not sure where some of the "closed" responses are coming from, but when I look at my PFSense logs, the ports that show "stealth" on GRC, show a logged event in PFSense, but the ports that show "closed" in GRC, do not show in my PFSense logs. Something else up-stream is responding. The only ports I get as "closed" are related to SMB. I assume my ISP is blocking remote SMB on their firewall.

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                                  • KOMK
                                    KOM
                                    last edited by

                                    0-1055 all stealth here.

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                                    • stephenw10S
                                      stephenw10 Netgate Administrator
                                      last edited by

                                      @johnpoz:

                                      Even a virus would not need 627 ports ;)

                                      Yeah, not exactly stealth. Worst. Virus. Ever.  ::)

                                      Seems more likely to be not actually scanning pfSense for whatever reason. CG-NAT perhaps?

                                      Steve

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                                      • K
                                        kejianshi
                                        last edited by

                                        I actually believe those results could be true.

                                        Post an IP.  I can scan it from here.  I'm sure a few of us could confirm if the results are good or not.

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                                        • H
                                          Harvy66
                                          last edited by

                                          @kejianshi:

                                          My thoughts exactly.  uPNP may be forwarding  (opening) ports you have not thought about.

                                          This is why I put int an explicit block on ports 1-1023. I don't want any pesky uPNP trying to do strange things.

                                          The biggest issue isn't uPNP, it's that I need to use NAT in the first place. Many games need to listen on ports, but because you can't have multiple clients all using the same ports, you can't know which ports will be used ahead of time. If port opening needs to be dynamically controlled by the client, how else does one handle this?

                                          My main concern isn't what my clients are trying to do, it's what the public Internet is trying to do to my clients. As long as standard service ports are not opened, I'm content. Home install, I'm not a network admin.

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                                          • johnpozJ
                                            johnpoz LAYER 8 Global Moderator
                                            last edited by

                                            No the issue is how UPnP is implemented without any security/auth that allows something to be opened, and ease of control of what that device can open, etc.  Most home routers give you no control at all.

                                            Not sure what your blocking - but inbound from the wan has all ports block out of the gate.  Where are you creating this 1-1023 block?

                                            While its true many ports need to listen on port - they sure shouldn't be < than 1023..  Where in the list of ports are there any games that have these ports registered?

                                            http://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.txt

                                            I don't see any games?  No game that I could think of should be listening on a PRIVILEGED port that is for sure..

                                            There is a SHIT load of ports to be used - how many games are you running that it should ever overlap, and people that design a game that is played over the internet and don't take into account the ability to control which ports are used are just not thinking if you ask me!!

                                            I have never ran into such a game.  All the issues go away soon with NAT you can hope as IPv6 is here - With lots of IPs to play with that removes the need of nat completely.  These games still do not need to listen on ports < 1023..  So from his listing 416 to 557 are OPEN..  Why would something open such a big range privileged..  If we look up those ports.

                                            example
                                            nnsp                433        tcp    NNSP

                                            This is port used for bulk transfers of NNTP between servers..  Why would some GAME use that port?  And since its under 1023 should require elveated permissions to even listen on that port, etc.

                                            If I ran across a scan showing such results - the first thing I would do is run the scan again while sniffing on wan and validate for starters that scan is actually hitting my IP and that responses are leaving my interface because its so out there it is highly unlikely there is anything actually listening on all those ports to have it show "OPEN"

                                            An intelligent man is sometimes forced to be drunk to spend time with his fools
                                            If you get confused: Listen to the Music Play
                                            Please don't Chat/PM me for help, unless mod related
                                            SG-4860 24.11 | Lab VMs 2.8, 24.11

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