Milan Airports answered that they have submitted the issue to the "Information technology staff"
source: https://twitter.com/pimterry/status/1192038174408753152?s=20
Milan Airport WiFi sends your MAC address to advertisers and trackers
11–20 of 64 posts
Re: Milan Airport WiFi sends your MAC address to advertisers and trackers
#12Does anyone have a theory on what the "advertisers and trackers" want a MAC address for? If they're using it for anything load bearing, it seems like there is an interesting CCC talk lurking here for anyone who wants to visit that airport with a few hundred dollars worth of devices and stuff a few tens of million spoofed MAC addresses into the system.
Since MAC address ranges are allocated to certain manufacturers, it is a simple way to track your device type. Additionally, all MAC addresses are unique so it is the easiest way to match/combine your data from different trackers.
> Additionally, all MAC addresses are unique so it is the easiest way to match/combine your data from different trackers.
This is not true. While it's intended for MAC addresses to be unique, there are plenty of instances where manufacturers re-use MACs when they run out instead of registering more.
Additionally, there is no issue with multiple devices having the same MAC address as long as they're never on the same Layer 2 domain.
Re: Milan Airport WiFi sends your MAC address to advertisers and trackers
#13The problem with constantly shuffling MAC addresses is that they are used for device authentication on corporate/school/university networks. Does anyone know of a utility that generates MAC addresses as a hash of the SSID?
A bash script?
You can scan for the networks in the area, select the one you want, run the name through, say sha256, select the first 8 characters and reset the mac address to that.
Re: Milan Airport WiFi sends your MAC address to advertisers and trackers
#14iPhones randomize the MAC address when connecting to hotspots (on a per-ssid basis, I think?). Other platforms do too (Windows 10 now has an option to do that automatically as well, but I can’t recall if it is enabled by default).
Recent NetworkManager versions on Linux do the same (I don't remember if it's on by default or not, though).
Re: Milan Airport WiFi sends your MAC address to advertisers and trackers
#15We can't be sure about this, maybe the airport mask the data to a relay
Re: Milan Airport WiFi sends your MAC address to advertisers and trackers
#16The problem with constantly shuffling MAC addresses is that they are used for device authentication on corporate/school/university networks. Does anyone know of a utility that generates MAC addresses as a hash of the SSID?
A bash script? You can scan for the networks in the area, select the one you want, run the name through, say sha256, select the first 8 characters and reset the mac address to that.
Yeah, not that hard to do manually--I have a nice script for that. But I haven't looked into the logistics of hooking into the wifi connection process and doing this automatically :)
Re: Milan Airport WiFi sends your MAC address to advertisers and trackers
#17Does anyone have a theory on what the "advertisers and trackers" want a MAC address for? If they're using it for anything load bearing, it seems like there is an interesting CCC talk lurking here for anyone who wants to visit that airport with a few hundred dollars worth of devices and stuff a few tens of million spoofed MAC addresses into the system.
Since MAC address ranges are allocated to certain manufacturers, it is a simple way to track your device type. Additionally, all MAC addresses are unique so it is the easiest way to match/combine your data from different trackers.
Right. I understand what MAC addresses are. In addition to the characteristics you named, they are also entirely at the discretion of the client and therefore are trivially spoofable so long as no one else on the same media currently has the address you're spoofing. And because the advertisers and the trackers are a step removed from the LAN, they have no way to detect an attack where someone just shits tens of millions of nonsense addresses at them.
So I'm suggesting that if we know what they are using those for, there could be something fun (like a CCC talk) to be gained from tainting their data in a creative, easy way. Like a few hundred dollars worth of junk devices in a suitcase sending a bunch of carefully crafted MACs :-)
Re: Milan Airport WiFi sends your MAC address to advertisers and trackers
#18Earlier quoted context omitted.
Since MAC address ranges are allocated to certain manufacturers, it is a simple way to track your device type. Additionally, all MAC addresses are unique so it is the easiest way to match/combine your data from different trackers.
Right. I understand what MAC addresses are. In addition to the characteristics you named, they are also entirely at the discretion of the client and therefore are trivially spoofable so long as no one else on the same media currently has the address you're spoofing. And because the advertisers and the trackers are a step removed from the LAN, they have no way to detect an attack where someone just shits tens of milli…
[deleted]
Re: Milan Airport WiFi sends your MAC address to advertisers and trackers
#19iPhones randomize the MAC address when connecting to hotspots (on a per-ssid basis, I think?). Other platforms do too (Windows 10 now has an option to do that automatically as well, but I can’t recall if it is enabled by default).
Recent NetworkManager versions on Linux do the same (I don't remember if it's on by default or not, though).
Yeah it's by default. Learned this the hard way when setting up port forwarding by MAC address on home network. Was wondering why the forward would only last a couple hours
Re: Milan Airport WiFi sends your MAC address to advertisers and trackers
#20Earlier quoted context omitted.
Since MAC address ranges are allocated to certain manufacturers, it is a simple way to track your device type. Additionally, all MAC addresses are unique so it is the easiest way to match/combine your data from different trackers.
Right. I understand what MAC addresses are. In addition to the characteristics you named, they are also entirely at the discretion of the client and therefore are trivially spoofable so long as no one else on the same media currently has the address you're spoofing. And because the advertisers and the trackers are a step removed from the LAN, they have no way to detect an attack where someone just shits tens of milli…
The amount of people who routinely spoof their own MAC when on public wifi is so minuscule to be objectively irrelevant to any mass-data-gatherer out there. Unless this becomes something that the OS can automatically randomize for you (are you listening, Apple...?), even a creative attack won’t move the needle.