O2 mobile users in the UK are venting on Twitter today, fuming at their discovery that their phone number is being shared with every website that they visit over the network.
I found a colleague who owns an iPhone on the O2 network, and we tried it out for ourselves. Making sure we turned off his WiFi connection, we used the O2 mobile network to access the web.
Sure enough, his mobile number was being secretly communicated to websites he visited, embedded inside an http header called HTTP_X_UP_CALLING_LINE_ID.
O2’s response so far is to tell concerned Twitter users that it is investigating the issue.
@lewispeckover we're investigating this as we speak with our internal teams, we'll get back to you as soon as possible.
— O2 in the UK (@O2) January 25, 2012
Well, maybe I can be of some assistance. Because, although the problem is getting a lot of people’s attention today, it’s actually been known about for almost two years at least.
Back in March 2010, Berlin student Collin Mulliner revealed his discovery at the CanSecWest conference in Vancouver and…
Read more in my article on the Naked Security website.