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    HEADS UP: Be aware of Trusted Recursive Resolver (TRR) in Firefox

    Scheduled Pinned Locked Moved DHCP and DNS
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    • johnpozJ
      johnpoz LAYER 8 Global Moderator
      last edited by johnpoz

      So I found this listing of known doh servers
      https://github.com/curl/curl/wiki/DNS-over-HTTPS#publicly-available-servers

      I have a pm out of @BBcan177 asking if he plans on easy way of blocking these in pfblocker, if not will be working my own listing of them to use in firewall rules and host overrides to block queries for them.

      Will prob have dns queries for their fqdn point to a specific IP that I block and log, and any hits to that rule get attention and any devices doing it will if not easy to disable be off the network..

      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

      BBcan177B 1 Reply Last reply Reply Quote 0
      • JeGrJ
        JeGr LAYER 8 Moderator
        last edited by JeGr

        I'd also use

        local-zone: "use-application-dns.net" static

        in the DNS Resolver "custom options" box so to answer with an NXDOMAIN to the canary domain Mozilla uses. Won't help if they switch their approach or simply use a service manually entered but at least the "automagic switch" should be off then.

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

        If you're interested, I'm available to discuss details of German-speaking paid support (for companies) if needed.

        1 Reply Last reply Reply Quote 0
        • johnpozJ
          johnpoz LAYER 8 Global Moderator
          last edited by johnpoz

          Yeah been in place for some time already ;)

          Notice I posted how to do it like 8 days ago ;) Look back over the thread..

          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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          • BBcan177B
            BBcan177 Moderator @johnpoz
            last edited by

            @johnpoz said in HEADS UP: Be aware of Trusted Recursive Resolver (TRR) in Firefox:

            I have a pm out of @BBcan177 asking if he plans on easy way of blocking these in pfblocker, if not will be working my own listing of them to use in firewall rules and host overrides to block queries for them.

            Some more details here for now until I add this officially to pfBlockerNG:

            https://www.reddit.com/r/pfBlockerNG/comments/d3p1gf/doh_server_blocklist/

            "Experience is something you don't get until just after you need it."

            Website: http://pfBlockerNG.com
            Twitter: @BBcan177  #pfBlockerNG
            Reddit: https://www.reddit.com/r/pfBlockerNG/new/

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            • johnpozJ
              johnpoz LAYER 8 Global Moderator
              last edited by johnpoz

              Thanks - but you the have the
              use-application-dns.net

              In there - that would not return an NX, so it wouldn't work per my understanding of how the firefox canary is suppose to work.. It has to get back a NX to not enable it from my understanding.

              I threw this together real quick this morning from list linked to earlier.

              local-data: "dns.adguard.com. 120 IN A 172.19.19.19"
local-data: "dns-family.adguard.com. 120 IN A 172.19.19.19"
local-data: "dns.google. 120 IN A 172.19.19.19"
local-data: "cloudflare-dns.com. 120 IN A 172.19.19.19"
local-data: "dns.quad9.net. 120 IN A 172.19.19.19"
local-data: "dns9.quad9.net. 120 IN A 172.19.19.19"
local-data: "dns10.quad9.net. 120 IN A 172.19.19.19"
local-data: "doh.opendns.com. 120 IN A 172.19.19.19"
local-data: "doh.cleanbrowsing.org. 120 IN A 172.19.19.19"
local-data: "dns.nextdns.io. 120 IN A 172.19.19.19"
local-data: "dns.dnsoverhttps.net. 120 IN A 172.19.19.19"
local-data: "doh.crypto.sx. 120 IN A 172.19.19.19"
local-data: "doh.powerdns.org. 120 IN A 172.19.19.19"
local-data: "doh-ch.blahdns.com. 120 IN A 172.19.19.19"
local-data: "doh-jp.blahdns.com. 120 IN A 172.19.19.19"
local-data: "doh-de.blahdns.com. 120 IN A 172.19.19.19"
local-data: "dns.dns-over-https.com. 120 IN A 172.19.19.19"
local-data: "doh.securedns.eu. 120 IN A 172.19.19.19"
local-data: "dns.rubyfish.cn. 120 IN A 172.19.19.19"
local-data: "doh-2.seby.io. 120 IN A 172.19.19.19"
local-data: "doh.seby.ie. 120 IN A 172.19.19.19"
local-data: "commons.host. 120 IN A 172.19.19.19"
local-data: "doh.dnswarden.com. 120 IN A 172.19.19.19"
local-data: "dns-nyc.aaflalo.me. 120 IN A 172.19.19.19"
local-data: "dns.aaflalo.me. 120 IN A 172.19.19.19"
local-data: "doh.appliedprivary.net. 120 IN A 172.19.19.19"
local-data: "doh.captnemo.in. 120 IN A 172.19.19.19"
local-data: "doh.tiar.app. 120 IN A 172.19.19.19"
local-data: "doh.dns.sb. 120 IN A 172.19.19.19"
local-data: "rdns.faelix.net. 120 IN A 172.19.19.19"
local-data: "doh.li. 120 IN A 172.19.19.19"
local-data: "doh.armadillodns.net. 120 IN A 172.19.19.19"
local-data: "doh.netweaver.uk. 120 IN A 172.19.19.19"
local-data: "jp.tiar.app. 120 IN A 172.19.19.19"
local-data: "doh.42l.fr. 120 IN A 172.19.19.19"

              Here is sample query for one of those.

              ;; QUESTION SECTION:
;doh.dns.sb.                    IN      A

;; ANSWER SECTION:
doh.dns.sb.             120     IN      A       172.19.19.19

              Simple add that to your custom box in unbound, then put a block log rule in place that logs anything that tries to go to my out of thin air IP that I do not use locally 172.19.19.19

              This way I can see if anything is trying to resolve this by just looking if any hits in the firewall rules, and then look into the logs to which IP tried and investigate what its trying to do exactly.

              Keep in mind, this could cause you some grief if any of those fqdn are serving up stuff other than doh that you might want to get to.. Some are on other ports other then 443, so I just made the block rule any..

              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

              1 Reply Last reply Reply Quote 0
              • kiokomanK
                kiokoman LAYER 8
                last edited by

                bind9

                $TTL 60
@            IN    SOA  localhost. root.localhost.  (
                      2019091601
                      3H  ; refresh
                      1H  ; retry
                      1W  ; expiry
                      1H) ; minimum
              IN    NS    localhost.

; Make TRR unavailable
dns.adguard.com 120 IN CNAME  .
dns-family.adguard.com 120 IN CNAME  .
dns.google 120 IN CNAME  .
cloudflare-dns.com 120 IN CNAME  .
dns.quad9.net 120 IN CNAME  .
dns9.quad9.net 120 IN CNAME  .
dns10.quad9.net 120 IN CNAME  .
doh.opendns.com 120 IN CNAME  .
doh.cleanbrowsing.org 120 IN CNAME  .
dns.nextdns.io 120 IN CNAME  .
dns.dnsoverhttps.net 120 IN CNAME  .
doh.crypto.sx 120 IN CNAME  .
doh.powerdns.org 120 IN CNAME  .
doh-ch.blahdns.com 120 IN CNAME  .
doh-jp.blahdns.com 120 IN CNAME  .
doh-de.blahdns.com 120 IN CNAME  .
dns.dns-over-https.com 120 IN CNAME  .
doh.securedns.eu 120 IN CNAME  .
dns.rubyfish.cn 120 IN CNAME  .
doh-2.seby.io 120 IN CNAME  .
doh.seby.ie 120 IN CNAME  .
commons.host 120 IN CNAME  .
doh.dnswarden.com 120 IN CNAME  .
dns-nyc.aaflalo.me 120 IN CNAME  .
dns.aaflalo.me 120 IN CNAME  .
doh.appliedprivary.net 120 IN CNAME  .
doh.captnemo.in 120 IN CNAME  .
doh.tiar.app 120 IN CNAME  .
doh.dns.sb 120 IN CNAME  .
rdns.faelix.net 120 IN CNAME  .
doh.li 120 IN CNAME  .
doh.armadillodns.net 120 IN CNAME  .
doh.netweaver.uk 120 IN CNAME  .
jp.tiar.app 120 IN CNAME  .
doh.42l.fr 120 IN CNAME  .

                i can change the dot to some "out of thin air ip" if i want to log, reporting NX for the moment

                laboratorio@server:/$ dig @127.0.0.1 doh.crypto.sx

; <<>> DiG 9.11.3-1ubuntu1.9-Ubuntu <<>> @127.0.0.1 doh.crypto.sx
; (1 server found)
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 10547
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 2

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
; COOKIE: dda6e2c23949f6cda855e6485d7fa7fddeb8459af20d8f8b (good)
;; QUESTION SECTION:
;doh.crypto.sx.                 IN      A

;; ADDITIONAL SECTION:
overrides.              60      IN      SOA     localhost. root.localhost. 2019091601 10800 3600 604800 3600

;; Query time: 4 msec
;; SERVER: 127.0.0.1#53(127.0.0.1)
;; WHEN: Mon Sep 16 17:19:25 CEST 2019
;; MSG SIZE  rcvd: 129

                ̿' ̿'\̵͇̿̿\з=(◕_◕)=ε/̵͇̿̿/'̿'̿ ̿
                Please do not use chat/PM to ask for help
                we must focus on silencing this @guest character. we must make up lies and alter the copyrights !
                Don't forget to Upvote with the 👍 button for any post you find to be helpful.

                1 Reply Last reply Reply Quote 1
                • johnpozJ
                  johnpoz LAYER 8 Global Moderator
                  last edited by johnpoz

                  Only reason pointed it to an IP, is I normally don't log dns queries - there are so freaking many of them it can be information overload to weed through... I only enable dns query logs when wanting to troubleshoot a specific issue.

                  Figured if I point it to a specific IP, I can log any attempted access to that odd IP so can see at a glance in the firewall interface if any hits to it. And then investigate..

                  Multiple ways to skin the cat is best, so no matter what what users are using specific in there setups they have a easy way to skin this one..

                  These little devices could bypass these method with a direct query to the IP.. So prob need to put together an alias that lists the actual public IPs and blocks.. This is going to turn into such a shit show..

                  Uncontrolled circumvention of a local networks controls is not by any stretch of the imagination good for anyone!

                  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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                  • JeGrJ
                    JeGr LAYER 8 Moderator
                    last edited by

                    Was just shown this by colleague: https://bsd.network/interact/102767562311572315
                    Had to laugh ;)

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

                    If you're interested, I'm available to discuss details of German-speaking paid support (for companies) if needed.

                    1 Reply Last reply Reply Quote 4
                    • R
                      Repo
                      last edited by

                      This resolver now points to https://mozilla.cloudflare-dns.com/dns-query instead of https://cloudflare-dns.com/dns-query

                      1 Reply Last reply Reply Quote 0
                      • JeGrJ
                        JeGr LAYER 8 Moderator
                        last edited by

                        @JeGr said in HEADS UP: Be aware of Trusted Recursive Resolver (TRR) in Firefox:

                        canary

                        But the canary stayed the same, so that should already disable it.

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

                        If you're interested, I'm available to discuss details of German-speaking paid support (for companies) if needed.

                        1 Reply Last reply Reply Quote 0
                        • NollipfSenseN
                          NollipfSense
                          last edited by

                          I have been reading this thread and have added the list found in the link that BBcan177 provided above to DNSBL. However, where is the about:config mentioned by Jim so I can set network.trr.mode to 5? This is what I saw in Firefox preference:
                          Screen Shot 2019-10-06 at 1.05.22 PM.png

                          pfSense+ 23.09 Lenovo Thinkcentre M93P SFF Quadcore i7 dual Raid-ZFS 128GB-SSD 32GB-RAM PCI-Intel i350-t4 NIC, -Intel QAT 8950.
                          pfSense+ 23.09 VM-Proxmox, Dell Precision Xeon-W2155 Nvme 500GB-ZFS 128GB-RAM PCIe-Intel i350-t4, Intel QAT-8950, P-cloud.

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                          • johnpozJ
                            johnpoz LAYER 8 Global Moderator
                            last edited by

                            in the about:config section

                            aboutconfig.png

                            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

                            NollipfSenseN 1 Reply Last reply Reply Quote 1
                            • NollipfSenseN
                              NollipfSense @johnpoz
                              last edited by

                              @johnpoz Thanks John for responding...it seems that Macs don't have that options...I am using Firefox 69.0.2...

                              Screen Shot 2019-10-06 at 2.33.59 PM.png

                              pfSense+ 23.09 Lenovo Thinkcentre M93P SFF Quadcore i7 dual Raid-ZFS 128GB-SSD 32GB-RAM PCI-Intel i350-t4 NIC, -Intel QAT 8950.
                              pfSense+ 23.09 VM-Proxmox, Dell Precision Xeon-W2155 Nvme 500GB-ZFS 128GB-RAM PCIe-Intel i350-t4, Intel QAT-8950, P-cloud.

                              1 Reply Last reply Reply Quote 0
                              • johnpozJ
                                johnpoz LAYER 8 Global Moderator
                                last edited by johnpoz

                                I don't have a mac to test with.. But your at about:preferences not about:config?

                                No you wouldn't find it there - see I went there in my windows firefox

                                firefoxpref.png

                                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

                                NollipfSenseN 1 Reply Last reply Reply Quote 0
                                • NollipfSenseN
                                  NollipfSense @johnpoz
                                  last edited by

                                  @johnpoz Found it John...one has to type about:config in the URL bar and accept the risk...thank you!

                                  Screen Shot 2019-10-06 at 3.01.32 PM.png

                                  pfSense+ 23.09 Lenovo Thinkcentre M93P SFF Quadcore i7 dual Raid-ZFS 128GB-SSD 32GB-RAM PCI-Intel i350-t4 NIC, -Intel QAT 8950.
                                  pfSense+ 23.09 VM-Proxmox, Dell Precision Xeon-W2155 Nvme 500GB-ZFS 128GB-RAM PCIe-Intel i350-t4, Intel QAT-8950, P-cloud.

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                                  • H
                                    HuskerDu
                                    last edited by HuskerDu

                                    I've just tried the unbound custom option... it seems Firefox keeps asking for its DoH stuff, Suricata seeing some associated traffic.

                                    1	TCP	A Network Trojan was Detected	10.X.X.X 51133	104.16.249.249 443	1:2027695 ET POLICY Observed Cloudflare DNS over HTTPS Domain (cloudflare-dns .com in TLS SNI)
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                                    • johnpozJ
                                      johnpoz LAYER 8 Global Moderator
                                      last edited by

                                      Did you set TRR in firefox to 5? Without some details of what you actually did there is little anyone can do to help you find out what you did wrong.

                                      You need to make sure unbound return NX..

                                      nx.jpg

                                      I watch this like a hawk and have rules in place to log any sort of doh to any of the know ns doing doh, and block tos - and have not seen any hits on the rules at all.

                                      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

                                      1 Reply Last reply Reply Quote 0
                                      • H
                                        HuskerDu
                                        last edited by

                                        The purpose was to test the usage that Firefox makes of its canary domain and if it obey their published rules.

                                        First of all, the status is NOERROR not NXDOMAIN

                                        ; <<>> DiG 9.10.6 <<>> use-application-dns.net
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 27411
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;use-application-dns.net.	IN	A

;; ANSWER SECTION:
use-application-dns.net. 60	IN	A	10.10.10.1

;; Query time: 45 msec
;; SERVER: 10.0.0.1#53(10.0.0.1)
;; WHEN: Tue Nov 26 21:31:02 CET 2019
;; MSG SIZE  rcvd: 68

                                        TRR was 2 as it was the intend of that quick test.

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                                        • johnpozJ
                                          johnpoz LAYER 8 Global Moderator
                                          last edited by johnpoz

                                          Well that is not how canary is meant to work - so yeah it would fail... It needs to return NX..

                                          https://support.mozilla.org/en-US/kb/canary-domain-use-application-dnsnet

                                          You returned no error and A record... So yeah its going to be able to use doh.

                                          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

                                          1 Reply Last reply Reply Quote 0
                                          • H
                                            HuskerDu
                                            last edited by HuskerDu

                                            I've changed

                                            local-zone: "use-application-dns.net" static

                                            to

                                            local-zone: "use-application-dns.net" always_nxdomain

                                            And it now works

                                            ; <<>> DiG 9.10.6 <<>> use-application-dns.net
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 58414
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;use-application-dns.net.	IN	A

;; Query time: 37 msec
;; SERVER: 10.0.0.1#53(10.0.0.1)
;; WHEN: Wed Dec 04 20:16:56 CET 2019
;; MSG SIZE  rcvd: 52

                                            Well kind of, Suricata keeps logging the same alert (ET POLICY Observed Cloudflare DNS over HTTPS Domain (cloudflare-dns .com in TLS SNI))

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