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.
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
Besides the MAC lookup suggestion, have you tried to simply find hostname in local DNS by reverse IP lookup, maybe that would shed some light.
Not sure if there is anything useful, but in browser just check site source, maybe there is something useful there that could help with identification. Does site have certificate? It might include info that would help with identification. Do the standard browser network trace via dev tools F12, maybe something useful appears there.
In nmap you can attempt to guess OS, try that. Additionally it might be possible to get hostname as well.
And have you checked your router to see if this connection is connected to your Wi-Fi AP or Ethernet to narrow things down? If it is not possible to determine this from router, simply connect your main PC to Ethernet, disable AP in router settings and check if IIS site is still up. If it is not, enable AP again, does it come back early or it takes some time?
Lastly, if it still is a mystery, start powering off devices one by one to find the source. Based on comments it seems you have multiple devices, but I assume it would not take that long?
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?
There are Ethernet extenders that can utilize the power lines. They basically plug into an outlet and you stick an Ethernet into them and do the same somewhere else in the house.
Exactly, except mine was talking to the neighbors :p
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?
Maybe try traceroutre or lft (layer 4 traceroutre) to see if something wacky is happening with routing in your lan?
You’re looking at my worst nightmare 😅
I would download metasploit and dig up some interesting exploits to try against it.
It’s me. I’m your nextdoor neighbour. Sorry!
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.
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
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
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/
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.
Thanks!
Did this actually help?
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).
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:
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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)
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Are you running a VPN server or using VPN to bridge any networks?
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You said you’re running dual WAN, are those configured properly and not leaking random internet shit into your LAN?
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Do you have anything that might be running some kind of out-of-band management system like DRAC on a dell server?
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What’s your IoT situation?
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Do you have an on-site NVR for security cams?
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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 :)
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You should try running the original command with elevated privileges,
sudo nmap ...
on linux.What’s weird about this is that it should be getting a response from IIS like you showed us in the screenshot.
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?
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.
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.
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?
I have quite a few smart home devices. But the only “crappy IoT things” is an air purifier that is controlled by phone.
Unfortunately, I bought quite a few T-Link products before the IC revealed that they are dangerous.
It is worth exploring.
Edit TP-Link
Ah I have a TP-link router as well, two actually, and Im not monitoring my home network at all. Your experience makes me think I should!
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?
Great Idea! My windows box is off and I can still see it from my phone.
Hmm
I’d maybe try systematically turning any other devices off you think could potentially have the grunt to run windows server in a container or VM.
Do you have a Mac/Linux machine handy? If you run
arp -a
in one terminal and ping the unusual IP in another, that should give you a corresponding MAC address for the device. You can then look up the MAC address and see if it gives you any more info about the device running it—it might not but you never know. You can use something like https://dnschecker.org/mac-lookup.phpI guess next you could look at taking that MAC and blocking it in your router control panel and see if anything starts complaining
I guess next you could look at taking that MAC and blocking it in your router control panel and see if anything starts complaining
I love the “see who screams” method, my coworkers do not. it’s usually instant.
In addition, you might like to do a portscan on that IP address to see if any other ports reaveal something more interesting.
You can run this in cmd prompt, I think, if nmap is available on your windows machine:
nmap -p 1-9999 192.168.1.1
IIS can only run on a windows OS, so it must be a windows physical machine or VM connected to your network.
Thanks as you can tell, I’m not an expert in any of this.
I will run this as you described.
I did the nmap based on input from ChatGPT, it had me do a Ping base scan with nmap. It turned up nothing because that IP address did not return a Ping.
This has me really curious.
I’m concerned that the website I opened in Safari on my phone is bringing up a cache on my browser and is not actually live.
I tried to open it from an iPad and it did not load. Iit still loads off my phone even though I have rebooted everything.
In case it helps your troubleshooting, ICMP (ping) is typically disabled by default on Windows.
That is weird. Running development environments maybe? Docker with windows iis?
I have x-code loaded on a Mac, but that is the closest I have to that.
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
Even if it isn’t changing IP, you still want it in your DHCP table so that IP doesn’t accidentally get assigned to something else. It’s unlikely on a small network but it can happen.
Thanks! I did not know DHCP allocation was optional on a home network.
“home” isn’t descriptive enough. you can run some VERY powerful, in depth stuff if you were so inclined on a “home” network.
It is more than your average home network. I have a dual WAN router with fiber on each to a different provider. (It is stupid overkill, but my wife and I both work from home and it is important not to be down). I use a pi-hole for ad blocking and unbound for recursive DNS resolution. Most of the devices are wired Ethernet, so I have a bunch of switches and kit to transform coax into fast Ethernet.
I don’t mess with the firewalls, because that seems like there is a big downside to messing about if you get it wrong. That is all vanilla out of the box.
nice. firewalls are easy though, most you can keep vanilla. if you’ve setup a pihole, configuring a firewall is a breeze. most are all in ones also, so the router/gateway/firewall is all one box, just plug in your modem, then it’s a big switch basically with lots of options.
I run a ubiquiti usg pro 4, first gen and have a 24 port ubiquiti switch and access points. I love it. super advanced users will complain about some things, but ultimately it’s perfectly fine for me without having to get meraki $tuff. I run a few small game servers, a seedbox and some vms, nothing crazy. it moves about 1 TB / day of data from various torrents and nzbs, soulseek. have a micro Dell PC setup as my DNS and pihole, Plex server thousands of movies/shows.
The default home page for Microsoft IIS, the web server built into Windows Server (and probably some desktop builds too).
Windows 8 is starting to break out
lol!