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    Getting Potential DNS Rebind attack when accessing the public IP of a web server

    Scheduled Pinned Locked Moved DHCP and DNS
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    • N
      nosrepmodnar
      last edited by

      I have tried many of the things I found when searching the DNS rebind error along with pfSense.
      We are using 2.2.5.
      Have the public IP forwarding to a web server sitting on the LAN. Microsoft a-d and 2012 web server.
      When anyone outside goes to the web address t works fine.
      When a user at the local LAN goes to the web address they get the Potential DNS Rebind attack detected, see http://en.wikipedia.org/wiki/dns_rebinding. Try accessing the router by IP address instead of by hostname.

      I am not trying to address the router, I am trying to address the webserver.

      I checked the disable DNS binding checks and it then pulls up the router webgui when hitting the public IP.

      Not using DNS on the router so setting the rebind-domain-ok  command in the dns forwarder and private domain in the resolver didn't do anything.
      I also tried enabling them both with the settings and it made no difference.

      Any other suggestions?
      Thanks.

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      • N
        nosrepmodnar
        last edited by

        I retried a couple of things and this time it worked.
        I do not like it when things work sometimes and not others, but oh well.
        Anyways, created a DNS forwarder zone to the web address and the internal clients now leave the router alone.
        Thanks

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        • C
          cmb
          last edited by

          You don't want to disable that. Split DNS, or NAT reflection, is what you want.
          read the bottom of:
          https://doc.pfsense.org/index.php/DNS_Rebinding_Protections

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