Another day, another item of news about unwarranted state surveillance from the desk of one E. Snowden, late of Moscow.
This time the allegation is that Communications Security Establishment Canada (CSEC) slurped information about the owners of wireless devices from the free WiFi service in one of the nation's airports. With that data in hand, the agency is said to have then tracked travellers for “days” after they left the airport.
The Canadian Broadcasting Corporation (CBC) has the story and says it comes from “A top secret document retrieved by U.S. whistleblower Edward Snowden and obtained by CBC News”.
Snowden's documents apparently say anyone that passed through an airport could be tracked, although it is not clear if login to the free WiFi service was required. Logging in wouldn't necessarily be required to track someone: a device set to detect the presence of WiFi networks is likely to reveal its MAC address. If spooks sniffed WiFi routers for MAC addresses of connecting devices, then looked for that MAC address popping up elsewhere, they could easily plot a device's movement.
(Yes, we know that MAC addresses an oddity because they are supposed to be unique but can also be changed to a value used in another device. Changing MAC address is therefore a fine way to make it harder to identify a device, but is not the kind of thing most people who pass through airports would know about.)
The usual oohing and aahing that follows a Snowden release is now rippling across the Web. CESC is pointing out that it is allowed to collect communications metadata (which explains now sniffing a MAC address in an airport could translate into wider tracking). Canadians are expressing shock that their own government spied on them.
Making things more interesting is that the head of CSEC recently said the agency does not surveil Canadians. If CSEC was able to sort citizens from visitors at an airport just by sniffing WiFi-enabled devices, that could be the most damaging revelation of all! ®