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    No access to webinterface "Potential DNS Rebind attack detected" since July/3

    Scheduled Pinned Locked Moved 2.0-RC Snapshot Feedback and Problems - RETIRED
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    • M
      mxx
      last edited by

      Yes, I'm excited already ;)

      BTW: was just referring to "Have you tried with a snapshot from the 5th or preferably the 6th?"

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      • jimpJ
        jimp Rebel Alliance Developer Netgate
        last edited by

        Especially since I had to stop the builder and restart it again, we found several more bugs and cases to test for in that code.

        If you need the fixes, pull in the code with the fetch command I mentioned above and it should be OK.

        Remember: Upvote with the ๐Ÿ‘ button for any user/post you find to be helpful, informative, or deserving of recognition!

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        • M
          mxx
          last edited by

          Hey, thnx very much.
          I for myself will stick to 30th June Snapshot in the meanwhile.

          Thnx for all the hard work!

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          • ?
            Guest
            last edited by

            This may be a Potential DNS Rebind attack not an issue with pfsense. Do an nslookup or dig of google.com or twitter.comย  Use multiple DNS servers other than your own as well as the router.

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            • jimpJ
              jimp Rebel Alliance Developer Netgate
              last edited by

              @zarthan:

              This may be a Potential DNS Rebind attack not an issue with pfsense. Do an nslookup or dig of google.com or twitter.comย  Use multiple DNS servers other than your own as well as the router.

              No, we actually added a bunch of code to protect against DNS rebind attacks that would affect the web interface, but the checks needed some work. They should be OK in the next snapshot that comes out.

              Remember: Upvote with the ๐Ÿ‘ button for any user/post you find to be helpful, informative, or deserving of recognition!

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              • K
                kpa
                last edited by

                If you have an account at OpenDNS.com (and not just using their forwarders) you can have RFC1918 responses filtered out automatically, effectively disabling all DNS rebind attacks.

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                • jimpJ
                  jimp Rebel Alliance Developer Netgate
                  last edited by

                  @kpa:

                  If you have an account at OpenDNS.com (and not just using their forwarders) you can have RFC1918 responses filtered out automatically, effectively disabling all DNS rebind attacks.

                  There is a checkbox in the current repo code to disable these checks entirely if you want :-)

                  Remember: Upvote with the ๐Ÿ‘ button for any user/post you find to be helpful, informative, or deserving of recognition!

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                  • M
                    mxx
                    last edited by

                    Hi again,

                    just to let you know: the current snapshot 20100706-2143 still doesn't allow me to access the webinterface via its ip address nor hostname :(

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                    • jimpJ
                      jimp Rebel Alliance Developer Netgate
                      last edited by

                      @mxx:

                      Hi again,

                      just to let you know: the current snapshot 20100706-2143 still doesn't allow me to access the webinterface via its ip address nor hostname :(

                      What type of snapshot or update file is that? I'm not seeing any files with that timestamp.

                      Are you running the GUI on a standard port? Any kind of port forwarding involved?

                      Does it work after you do the fetch command I mentioned earlier in this thread?

                      Remember: Upvote with the ๐Ÿ‘ button for any user/post you find to be helpful, informative, or deserving of recognition!

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                      • M
                        mxx
                        last edited by

                        I used http://snapshots.pfsense.org/FreeBSD_RELENG_8_1/i386/pfSense_HEAD/updates/pfSense-Full-Update-2.0-BETA3-20100706-2143.tgz

                        That's the latest one I've found.

                        I'm running the webif on a non standard port (5556). No port forwarding at all.

                        Sorry didn't try to download the inc file manually as I thought it would already have been built-in in this Snapshot.

                        I'll give that a try now!

                        Thank you!

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                        • jimpJ
                          jimp Rebel Alliance Developer Netgate
                          last edited by

                          It's possible that the snapshot didn't get all of the changes we checked in, I don't remember when it was started.

                          Remember: Upvote with the ๐Ÿ‘ button for any user/post you find to be helpful, informative, or deserving of recognition!

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                          • jimpJ
                            jimp Rebel Alliance Developer Netgate
                            last edited by

                            That snapshot does have the code for letting you in with the GUI on an alternate port, and I can put my WebGUI on that port and it works fine.

                            Is there something else different about how you access the GUI? A proxy involved somehow?

                            Remember: Upvote with the ๐Ÿ‘ button for any user/post you find to be helpful, informative, or deserving of recognition!

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                            Do not Chat/PM for help!

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                            • M
                              mxx
                              last edited by

                              Okay after that it does work when I use the wan ip to connect.
                              When I use the hostname I setup for that ip in our dns server hosted externally, it does not.
                              It's quite bothersome to differentiate all the ip addresses used by different boxes and 2 pfsense firewalls that's why I set them up..

                              Will this also get fixed or would I have to disable the feature completely?
                              You mentioned a switch to turn it off, could you please tell me where I can find it?

                              Thanks!

                              Edit: no proxy, really standard config.. really strange.. accessing it by its ip address before I pulled the file didn't work at all, though I cannot say for sure whether it was a browser cache issue, sorry. However access by using the ip address works, but not with its hostname.. though this hostname is fully resolveableโ€ฆ

                              Edit: ok, I'm sorry, the error might be that pfsense's locally configured fqdn doesn't match the forwarding in the external dns server, what do you think?
                              Edit 3: But the problem is that this fqdn isn't possible to be resolved it's just a local domain...
                              I'd really like to be able to access each of its wan if ips by hostname forwardings..
                              May changing its hostname afterwards have any possible negative impacts on anything? Haven't installed tinydns.. ?

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                              • jimpJ
                                jimp Rebel Alliance Developer Netgate
                                last edited by

                                We already thought of just that scenario. :-)

                                Go to System > Advanced, on the admin tab. Put your custom hostname in the "Alternate Hostnames" box.

                                Remember: Upvote with the ๐Ÿ‘ button for any user/post you find to be helpful, informative, or deserving of recognition!

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                                • M
                                  mxx
                                  last edited by

                                  Hahaha great!

                                  Thank you :)

                                  All the best,

                                  Max

                                  Edit: works like a charm

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                                  • M
                                    mxx
                                    last edited by

                                    Request: could you disable the feature by default or disable it until the first successful web login?
                                    The way it is now it was a bit complicated to install pfsense on a VM only accessible by dnat through another router.

                                    Thanks!

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                                    • jimpJ
                                      jimp Rebel Alliance Developer Netgate
                                      last edited by

                                      I doubt that's going to be possible because it would defeat the purpose.

                                      If you have a VM, usually you can stick another VM on its LAN. The only "official" way to get into the web interface to start with is from the LAN.

                                      If it doesn't work when accessing it via IP address, then that could probably be addressed, but we'd need a lot more info.

                                      Remember: Upvote with the ๐Ÿ‘ button for any user/post you find to be helpful, informative, or deserving of recognition!

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                                      • M
                                        mxx
                                        last edited by

                                        Yes I can stick its lan interface into another vswitch to set it up, but this is just one possible scenario where it's quite easy.

                                        I had a linux box in the lan accessible by its lan ip with one interface in a vswitch. Pfsense's lan if was connected to the same vswitch.
                                        Pfsense LAN IP: 192.168.20.1 -> vswitch
                                        Linux LAN IP: 192.168.0.30 -> LAN, 192.168.20.20 -> vswitch
                                        I set it up to dnat incoming requests on port 443 from the lan side, to 192.168.20.1 and to SNAT to 192.168.20.20

                                        When trying to connect via the linux box' lan ip from the lan side, I was greeted by dns rebind warning.. I edited config.xml and rebooted..

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                                        • jimpJ
                                          jimp Rebel Alliance Developer Netgate
                                          last edited by

                                          I'm going to commit a patch here in a while that will work if accessing by any IP, since the DNS rebinding issue only matters for hostnames.

                                          Though I'm considering adding a warning to the login screen if the IP isn't a local IP.

                                          Remember: Upvote with the ๐Ÿ‘ button for any user/post you find to be helpful, informative, or deserving of recognition!

                                          Need help fast? Netgate Global Support!

                                          Do not Chat/PM for help!

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                                          • M
                                            mxx
                                            last edited by

                                            Thanks!

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