No Stupid Questions @lemmy.world RestrictedAccount @lemmy.world 3mo ago

I found a weird IP address on my network that had transmitted an insanely small amount of data. I put the address in my browser and got this. what the heck am I looking at?

UPDATE 10/4 6:47 EDT

I have been going through all the comments. THANKS!!!!!! I did not know about the techniques listed, so they are extremely helpful. Sorry for the slow update. As I mentioned below, I got behind with this yesterday so work cut into my evening.

I ran a port scan. The first syntax, -p, brought no joy. The nmap software itself suggested changing to -Pn. That brought an interesting response:

nmap -Pn 1-9999 <Local IP Addr>

Starting Nmap 7.93 ( https://nmap.org ) at 2024-10-04 11:44 BST

Failed to resolve "1-9999". Nmap scan report for <Local IP Address> Host is up (0.070s latency). All 1000 scanned ports on 192.168.0.46 are in ignored states. Not shown: 990 filtered tcp ports (no-response), 10 filtered tcp ports (host-unreach) Nmap done: 1 IP address (1 host up) scanned in 6.03 seconds Just to be absolutely sure, I turned off my work computer (the only windows box on my network) and reran the same syntax with the same results.

As I read this, there is definitely something on my network running windows that is not showing up on the DHCP.

UPDATE 10/6

I am working through all these suggestions. I am sorry for the slow responses, but I have my hands full with family weekend. I will post more next tomorrow. But I did do one thing that has me scratching my head and wondering if this may be a wild goose chase.

I ran the nmap again per below with a completely fictional IP address within my normal range. It gave the exact same results:

nmap -A -T4 -p- -Pn <Fictional IP>

Starting Nmap 7.93 ( https://nmap.org ) at 2024-10-05 13:36 BST Nmap scan report for <Fictional IP>

Host is up (0.054s latency).

All 65535 scanned ports on <Fictional IP> are in ignored states.

Not shown: 65525 filtered tcp ports (no-response), 10 filtered tcp ports (host-unreach)

Service detection performed. Please report any incorrect results at https://nmap.org/submit/ .

Nmap done: 1 IP address (1 host up) scanned in 182.18 seconds

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100 comments

It's the default page for a Windows Server running IIS web server.
As everyone else has said this is the out of the box default page that comes with Microsoft IIS web server on windows server.

Though I feel like you'd know if you had a copy of windows server running on your network somewhere—is the IP in your usual network subnet?
- The only windows box on my network is my company laptop. It is on a different IP address than that one.
  
  It IS in my normal range, but it is NOT listed on my Router’s DHCP client list.
  
  Have you recently installed visual studio or are doing any .NET development? It could possibly be a containerised version of IIS
  
  If you completely turn off your windows device and try to access the IP from another device does it still resolve?
  
  That is weird. Running development environments maybe? Docker with windows iis?
  
  Yeah, that's a company server, specifically for the local network group
  
  It IS in my normal range, but it is NOT listed on my Router’s DHCP client list.
  
  Why would an internal server change IP all the time? DHCP is for silly things like laptops that turn on and off eleventy times a day
  
  Any device can decide to set it's own IP so that's not too far fetched. Have any IoT crap like a water softener or colorful lights or speakers or cameras?
- You can enable IIS on almost any windows flavor.
  
  https://helpdeskgeek.com/windows-10/install-and-setup-a-website-in-iis-on-windows-10/
  
  Fair point.
  
  As a note, I don't recall all of them saying 'Windows Server' in the top left of that page.
- I think you can enable IIS, or at least some version of it, under Windows Features for Windows 10 Pro/Edu installs.
  
  But someone can correct me if I'm wrong about that.
So, as others have saId this is just an unconfigured IIS server, which implies it's either a windows machine, or a windows based VM, well or someone put the default IIS files on another server, but that's unlikely.

When you say "weird" IP I'd wonder what you mean by that.

I think since it's probably a windows machine, from another windows machine typing nbtstat -A <ip> should give you the computer name and workgroup or domain they belong to. See if it matches anything you expect on your network.

If not, maybe it's time to change your WPA wifi key.
- At least get WPA2
  
  I don't even think my current wifi kit has WPA (1) as an option. It's WPA2 or 3 only I'm pretty sure.
- Thanks. I ran nbtstat and it came up empty.
  
  Edit: Also, I am big on wired networks. I mostly save WI-FI for smart and mobile devices. There is a lot of stuff on Ethernet that does not need a password.
  
  Hmm. That would mean it's likely one of the following (well perhaps more options, but these spring to mind)
  
  A windows machine that has the network set as a public network, or netbios specifically blocked on LAN.
  
  A windows machine that has all the netbios services disabled.
  
  Not a windows machine, or a container as others suggested that's running some kind of IIS install
  
  Not a windows machine at all but for some weird reason IIS files and a web server setup.
  
  I think you suggested in another comment, that it's not in your DHCP client list but has an IP in your normal range. Which suggests it is setup with a static IP. That is odd.
  
  Some other people suggested it could be a container that is using a real IP rather than the NAT that docker etc usually use. I do know that you can use real IPs in containers, I've done it on my NAS to get a "proper" linux install on top of the NAS lite linux that is provided. But I would have expected that you'd know about that, since it would require someone to actually choose the IP address to use.
  
  If you have managed switches you could find which port on which switch the MAC address (as found by lookuping up the arp record for the IP using arp -a) is on (provided the switch allows access to the forwarding tables). Of course, if they're on Wi-Fi it's only going to lead to the access point they're connecting to.
- It could be a configured one with the default greet page still up.
The default home page for Microsoft IIS, the web server built into Windows Server (and probably some desktop builds too).
Following, I want to know what god awful iot device this is. Refrigerator? Toaster oven? Vibrating dildo? The suspense is killing me
- Nobody wants windows on a vibrating dildo
  
  I mean, Windows already fucks us metaphorically
  
  Maybe I want my vibrating dildo to take an hour to load and come with spyware
Bro, you gotta keep us updated, I'm surprisingly invested in this now.
- I lost my entire morning to this yesterday. I had to work late to catch up. There are some good ideas in here I’m starting on now.
If you can, power stuff off and check if that web page is still available. Start with any Windows machines. It could be a virtual machine running inside of something else though.

Edit: here's how to disable that web server https://superuser.com/a/1377078 . I'd do that on any Windows machines as well.
- The mac address can also tell you the hardware vendor.
- I shut off my only windows machine and it is still there.
  
  I'd go around unplugging anything that might be connected to the network, like game consoles, smart TV, etc. It's unlikely, but maybe something has copied that same screen to throw you off.
does your router give you the MAC address of the device? You can look it up to see who manufactured it and then narrow down. This could be a device that has a web service running is all you are seeing right now.
- Don't need the router. If you're on windows or linux, you just ping the ip then enter 'arp -a <ip>' it will show the MAC address for the IP from your machine's arp cache.
- It does not show up on the DHCP table, nor does it reflect pings.
  
  You can always start looking at how to use WireShark to sniff the packets and learn more about what is coming and going from that system. WireShark can be a daunting tool but if you look at some videos or walk through you should be able to get a handle on how to make it reveal only the one devices network traffic
Windows IIS probably from around the time of windows 8 so maybe 2012. Probably running on either windows server 2012 (like exchange, an active directory domain controller, or if you are unlucky sharepoint) or some weirdly configured appliance running windows 8 ish enterprise.
- Thanks. This helps. My work computer is way newer than that. It makes me think it could be networking hardware. I have some kit that’s about that old.
This is where you find that shit is so bloated and pointlessly connected that it's running on a washing machine.
Others haven't suggested this yet, but a single device, like your laptop, even with one connection, can have two IPs.
- Thanks. It is neither the Ethernet nor the Wi-Fi on my windows laptop.,
  
  Don't just turn your devices off when testing - - unplug them. An off computer can still respond to network requests.
Home network or corporate?

Its a windows server, if you are using widows too you can try establishing a RDP connection with Remote Desktop Connection.
- Yeah and giving a potential attacker your account details while trying to log on?
  
  Eyeballing the login screen may give some insight, you're right that its probably unwise to try real creds if you don't recognize the server.
- It is a home network. Configured by someone who understands the basics, but is mostly following recipeies rather than having deep knowledge.
How insanely small was the transfer? Like 1 bit?
- 9 packets
There was an appliance where the wifi chip was at the end of the power cable, embedded inside the plug. From the outside, you couldn't really tell. It was there so radiation inside the box couldn't affect the wireless signal as much.

I can imagine some genius thinking it's a good idea to run a server from inside a cable or a connected home appliance.
- Sounds like purchasing got a deal on surplus spook gear.
Depending on your router, it could have a docker setup with Windows on it. I've seen some strange shit on cheap routers with far too much processing power and storage.
- I will probably have to shut all the devices off and put them back one by one. OMG that will take a long time.
Get the MAC address from the ARP table, and look up the OIN, should help you determine if it's virtual or physical, and if physical the type of NIC it's using.
- That gave nothing useful
  
  Sorry, I meant the OUI ( was going by memory ) . It's the part that you can look up that tells your what kind of device the MAC address belongs to.
  
  The first few octets of the Mac address are unique to a manufacturer. This may at least help narrow which device it is. You can look it up at https://macaddress.io/
nmap -A -T4 -p- <IP>
- This is interesting. I had to modify it to nmap -A -T4 -p- -Pn <IP>.
  
  It said the host is up with 0.077 seconds of latency. All 64k ports were scanned with 7 filtered tcp ports (host-unreachable) and the rest (no-response).
  
  What's weird about this is that it should be getting a response from IIS like you showed us in the screenshot.
  
  77ms of latency is pretty slow. Based off that I'd assume (but not rule out) that it's not: on the machine you used to run nmap, not on ethernet, probably wifi with a shitty connection
  
  So, some really dumb, likely irrelevant, questions that might spark an idea:
  
  Do you see anything weird connected in the wifi client list? (You said it wasn't given a dhcp lease, but it would still show as a wireless client even if it were static)
  
  Are you running a VPN server or using VPN to bridge any networks?
  
  You said you're running dual WAN, are those configured properly and not leaking random internet shit into your LAN?
  
  Do you have anything that might be running some kind of out-of-band management system like DRAC on a dell server?
  
  What's your IoT situation?
  
  Do you have an on-site NVR for security cams?
  
  Did you find the mac? If so what are the first 3 octets? Even if the vendor can't be found, there's always the chance some crazy ubernerd is going to recognize it. (If it's 00:d0:2c or 44:d9:e7 I got ya covered)
  
  Again, most of those are probably irrelevant, but throwing the thoughts out there :)
  
  You should try running the original command with elevated privileges, sudo nmap ... on linux.
That is IIS, all it means is you are probably talking to a windows server. Is the traffic encrypted? What port is it going to?
- Is the traffic encrypted?
  
  If it is, look at the certificate. Which hostname is it for primarily? Which SAN (Subject Alternative Name - basically a list of all other hostnames the certificate is valid for) are set, if any? Which Certificate Authority issued the certificate or is it self signed?
- It shows NOT SECURE in the browser window
You don't have Ethernet over power do you?

Fun story, I live in a townhome, I had so bizarre network issues going on. Not able to stream to TV etc. finally started unplugging shit. Unplugged the router and saw the computer still happily downloading something WTF! Turns out a neighbor also had Ethernet over power and devices were randomly connecting to their network. Crazy ass shit.
- I'm confused. Are you talking about power over ethernet or power-line ethernet?
Windows 8 is starting to break out
- lol!
Is your IP adres same as localhost and you are using Windows Pro, then probably IIS is installed on your device.
Maybe set up Kismet https://www.kismetwireless.net/

That'll show devices attempting to break in wirelessly
... So when you port scanned it, IIS was gone?
nmap's seeing the 1-9999 as the next argument (expecting an IP address). In -Pn, the n is a placeholder for the port numbers you want to scan, so you want -P1-9999
You're looking at my worst nightmare 😅

I would download metasploit and dig up some interesting exploits to try against it.
Maybe try traceroutre or lft (layer 4 traceroutre) to see if something wacky is happening with routing in your lan?

100 comments