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    [INFO] Critical denial of service vulnerability in OpenVPN servers

    Scheduled Pinned Locked Moved OpenVPN
    16 Posts 7 Posters 3.3k Views
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    • ?
      Guest
      last edited by

      We're already tracking.  You beat me here by about a minute.

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      • JeGrJ
        JeGr LAYER 8 Moderator
        last edited by

        Someone may correct me if I'm wrong but as far as I read that announcement here:

        -> https://community.openvpn.net/openvpn/wiki/SecurityAnnouncement-97597e732b

        this only matters if it is triggered by an tls-authenticated client. So as long as I offer no public service and only hand out VPN certs, users & passes to people of my own organization (and they don't loose their cert, user & pass), all that happens is that the daemon could be DOS'ed and isn't available anymore (so I restart the VPN daemon, look at the logfile who was the dumbhead that killed my server and kick his balls). Spoken with a grain of sarkasm of course ;)

        But other than that - if I'm not trying to run some kind of VPN mega-service with free public registration to my VPN server (and therefore hand out certs to my server to everyone), I don't see that as overly mission critical as it was hyped/announced before.

        Greets

        Don't forget to upvote 👍 those who kindly offered their time and brainpower to help you!

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        • jimpJ
          jimp Rebel Alliance Developer Netgate
          last edited by

          That is correct.

          Unless you're running a public VPN server or run with ONLY auth (no certs/tls) then you're safe.

          The OpenVPN client export package has been updated with the new installers as of yesterday afternoon, and the 2.2 snapshots should have the new version now as well, but it wouldn't warrant a new 2.1.x release.

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          • K
            kejianshi
            last edited by

            Yeah….  OpenVPN seems abit on the useless side unless it server is public.
            So, I'm guessing this effects a whole lot of people.
            I will upgrade now.

            EDIT:  Since "Now" seems too soon.  I will try again in a few hours...

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            • jimpJ
              jimp Rebel Alliance Developer Netgate
              last edited by

              No, not a "public" VPN server as in one open to the world. A "public" VPN server like PIA, VyprVPN, and so on that accepts public clients where anyone can get a certificate and authenticate.

              If it's a private VPN for just you or a company or so on and you don't hand out certs like candy, then you're fine.

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

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              • K
                kejianshi
                last edited by

                Hmmmm.  Seems like upgrading will be smart for me.  Thanks.
                Any other changes getting into 2.3.6?

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                • jimpJ
                  jimp Rebel Alliance Developer Netgate
                  last edited by

                  Not sure what all changed in OpenVPN 2.3.6, the OpenVPN site should have a changelog.

                  Since this is a DoS ONLY and NOT one that could lead to information disclosure, if someone is worried about their VPN server dying the Service Watchdog package could help. It would restart the VPN server if it is down.

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                  • J
                    Jamerson
                    last edited by

                    hi guys a questiions,
                    is this update requested from the Pfsense side or the client side ?
                    thank you

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                    • jimpJ
                      jimp Rebel Alliance Developer Netgate
                      last edited by

                      The server side is the one that really needs updated to fix the potential DoS.

                      Though the client export package has the new 2.3.6 installers already, you can update those as needed as well.

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

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                      • J
                        Jamerson
                        last edited by

                        @jimp:

                        The server side is the one that really needs updated to fix the potential DoS.

                        Though the client export package has the new 2.3.6 installers already, you can update those as needed as well.

                        i've checked the latest Openvpn client export on the Pfsense it shows version of 1.2.15 as attached picture.
                        is this the latest  version of Pfsense ?

                        external users are updated to 2.3.6 version

                        thanks

                        ![Pfsense -openvpn.jpg](/public/imported_attachments/1/Pfsense -openvpn.jpg)
                        ![Pfsense -openvpn.jpg_thumb](/public/imported_attachments/1/Pfsense -openvpn.jpg_thumb)

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                        • jimpJ
                          jimp Rebel Alliance Developer Netgate
                          last edited by

                          That is the version of the export package. That version of the export package does include the OpenVPN 2.3.6 installers.

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

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                          • K
                            kejianshi
                            last edited by

                            Its too bad that the current stable version of pfsense won't get a minor maintenance release for this… 
                            I'm not sure how far out the stable release of 2.2 is.

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                            • jimpJ
                              jimp Rebel Alliance Developer Netgate
                              last edited by

                              2.2 RC should be out by the end of the day tomorrow. Release won't be that far behind given the current bug list and what's left to do.

                              To put out a 2.1.x release we would have to bring 2.2 development to a complete halt and focus on backporting and testing things in 2.1.x again. It's not worth the effort for this with 2.2 so close.

                              Remember: Upvote with the 👍 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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                              • K
                                kejianshi
                                last edited by

                                Cool.  I wasn't expecting a release in the next 6 months.  I'm used to beta staying beta for a good long while.

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                                • P
                                  phil.davis
                                  last edited by

                                  I'm with jimp - the 2.2-BETA really has got out all the bugs I can think of in the parts I use. I also think that 2.2-RC will not need to live for long before an official release.

                                  As the Greek philosopher Isosceles used to say, "There are 3 sides to every triangle."
                                  If I helped you, then help someone else - buy someone a gift from the INF catalog http://secure.inf.org/gifts/usd/

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