Netgate Discussion Forum
    • Categories
    • Recent
    • Tags
    • Popular
    • Users
    • Search
    • Register
    • Login

    Am I being attacked?

    Scheduled Pinned Locked Moved General pfSense Questions
    29 Posts 7 Posters 4.1k Views 7 Watching
    Loading More Posts
    • Oldest to Newest
    • Newest to Oldest
    • Most Votes
    Reply
    • Reply as topic
    Log in to reply
    This topic has been deleted. Only users with topic management privileges can see it.
    • johnpozJ Online
      johnpoz LAYER 8 Global Moderator @stephenw10
      last edited by johnpoz

      @stephenw10 said in Am I being attacked?:

      extremely unlikely

      Most likely an understatement IMO... More likely to get hit by lightening as you were cashing your winning mega millions lottery ticket ;) On a clear sunny day..

      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
      • stephenw10S Offline
        stephenw10 Netgate Administrator
        last edited by

        Yup, an attack is extremely unlikely because the chances of it even getting to the target host are basically zero. So why bother.

        Steve

        1 Reply Last reply Reply Quote 0
        • S Offline
          spookymonkey @johnpoz
          last edited by spookymonkey

          @johnpoz I mean, this is how phishing emails work! =) Sorta like when an attacker has a foothold or access to an internal network and performs relay attacks against smb and other protocols to serve fake logins (e.g. Responder). I was just curious though if it was a known thing for attackers to craft packets for this purpose. I'll take your word for it though that this type of spoofing shouldn't be something to be concerned about from a security perspective!

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

            @spookymonkey a state bypass attack by spoofing the IP and source port along with sequence numbers and timestamps is not how "phishing" emails work ;) heheh

            You clicking a link in some email that you think is your bank asking you to "verify" info has nothing to do with spoofing an IP..

            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

            S 1 Reply Last reply Reply Quote 0
            • S Offline
              spookymonkey @stephenw10
              last edited by

              @stephenw10 That makes sense, much easier to get a user to execute a payload than playing the packet lottery as @johnpoz likes to call it =)

              1 Reply Last reply Reply Quote 0
              • S Offline
                spookymonkey @johnpoz
                last edited by

                @johnpoz Lol, true.

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

                  @spookymonkey if your interested in ways to bypass a firewall.. Here is a method..

                  https://www.securityweek.com/state-sponsored-cyberspies-use-sophisticated-server-firewall-bypass-technique

                  Keep in mind the server on the victim network was already exploited, and the firewall allowed legit traffic to it... The bad software on the server behind the firewall was just leveraging the open path to pass traffic back and forth to the bad guy via the already open gate.. Looking like legit traffic.

                  Something like this a ips might be able to catch such bad traffic - but quite often this traffic is inside a https tunnel, that IPS would not be able to see..

                  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

                  bmeeksB 1 Reply Last reply Reply Quote 1
                  • bmeeksB Offline
                    bmeeks @johnpoz
                    last edited by

                    @johnpoz said in Am I being attacked?:

                    @spookymonkey if your interested in ways to bypass a firewall.. Here is a method..

                    https://www.securityweek.com/state-sponsored-cyberspies-use-sophisticated-server-firewall-bypass-technique

                    Keep in mind the server on the victim network was already exploited, and the firewall allowed legit traffic to it... The bad software on the server behind the firewall was just leveraging the open path to pass traffic back and forth to the bad guy via the already open gate.. Looking like legit traffic.

                    Something like this a ips might be able to catch such bad traffic - but quite often this traffic is inside a https tunnel, that IPS would not be able to see..

                    The moral of this story (from the article) is don't open stuff like SSH on the WAN side of your firewall. The entire scenario outlined in the article @johnpoz linked started with a dictionary attack on the password of an SSH account that was allowed through the firewall over to the web server. Once the attacker was on the web server, it's pretty much game over at that point.

                    While it may be technically correct to say the traffic "bypassed the firewall", that is not really a fair way to describe the scenario in my view. The firewall was configured to allow HTTP(S) traffic, the "malware C2 traffic" was disguised as HTTP(S); ergo, the firewall allowed it. So "bypass the firewall" is not necessarily how I would characterize it.

                    This could have been prevented, or at least made much more difficult, by using certificate-based public key authorization with the SSH account on the web server; or even better, putting that remote access behind a VPN.

                    So while it makes for a nice sensational headline to say "bypass the firewall", the actual truth is a bit more mundane and common. Somebody allowed password-authenticated remote access through the firewall to trusted servers behind it. That was the original compromise path. After the attacker is inside your local network, you've lost the war.

                    JKnottJ 1 Reply Last reply Reply Quote 2
                    • JKnottJ Offline
                      JKnott @bmeeks
                      last edited by

                      @bmeeks said in Am I being attacked?:

                      The moral of this story (from the article) is don't open stuff like SSH on the WAN side of your firewall.

                      It should be don't use ssh with a password. Use passwordless ssh instead. Ssh supports that. You create a public/private key pair, to allow access.

                      PfSense running on Qotom mini PC
                      i5 CPU, 4 GB memory, 32 GB SSD & 4 Intel Gb Ethernet ports.
                      UniFi AC-Lite access point

                      I haven't lost my mind. It's around here...somewhere...

                      1 Reply Last reply Reply Quote 1
                      • First post
                        Last post
                      Copyright 2025 Rubicon Communications LLC (Netgate). All rights reserved.