Archive for the ‘Random Stuff’ Category

Fun with wifi security

Tuesday, June 18th, 2013

Not too long ago I was reading a piece on the interwebs called the beginners guide to breaking website security with nothing more than a Pineapple and that title is a direct link to the page on author Troy Hunt’s blog. It isn’t a piece of the technically faint hearted, so I’ll try for a quick summary; there’s an inexpensive device called the Pineapple that ruthlessly exploits how trusted wifi connections work. Wireless devices are constantly calling out to known connection points, so if your home router is called MyHomeNet, when the mobile device you have connected to it in the house is out and about it’s periodically calling “is MyHomeNet there” into the ether to see if the router is around to make a connection… and the Pineapple listens for these calls and responds, pretending to be whatever Service Set Identification (SSID from here onwards) the device is asking for. Strap that to a laptop running Wireshark, share internet connectivity through another network connection and you’ve got a “man in the middle” listening post watching unsuspecting peoples’ traffic.

That’s quite alarming, but although I’m usually a lovely, fluffy bunny it also set the more nefarious, black hat wearing side of my mind working; fast food restaurants, coffee shops, hotels and even supermarkets offer free wireless and many of these access points appear as unencrypted networks; that connection pushes the user to a landing page where they enter a mobile number, which is then texted a code that unlocks the service. But as noted, the access point itself in these systems just appears as an unsecured wireless network so what happens if a mobile device configured to log in automatically on one of these services comes across another network with a matching SSID?

1337 H4x0R

Here’s my 1337 h4x0r rig to look into that question and yes, that’s sarcasm because it’s thrown together from scrap and spares. I’m using a battered Acer TravelMate 2350 which was dropped and half killed in a former life, connected to a D-Link wireless router which has been configured to broadcast the SSID of a national supermarket chain’s free wifi service. And when this pile of junk went online, my old Blackberry Curve which had previously been taught the same SSID from one of the supermarket’s access points earlier in the day automatically connected with absolutely no questions asked!

So what can we take away from this apart from a nagging paranoia? Well, anybody who works in IT has probably known for a while that wifi security is at best adequate and anybody with the right tools but no morals can at least theoretically crack into your router or access point if the shared pass phrase is weak enough. And television programmes like The Real Hustle have demonstrated how con artists use wifi, but this is in a way that requires marks to connect to a bogus SSID so the grifter risks discovery by placing themselves in or near the location of the network they’re spoofing (here’s a clip and this is really worth a watch if you use a laptop or other mobile device when traveling).

But what the Pineapple does is a different matter, it works anywhere and abuses the trust wireless devices have when it comes to networks so users can just be wandering along and minding their own business whilst the connection is made to their mobile device and all traffic for social media or email starts going through a monitored connection. The golden rules seem to be don’t let your mobile devices remember shared networks like the ones in public places (so delete the connection when you’re finished and that goes for the Apple Demo network some Apple stores use to demonstrate wifi use to their customers), turn off the device’s wifi completely when not using it and don’t use public connections to log into email accounts, online banking, Paypal, eBay, forums or anything else where losing control of the account would be a bad thing.

Parental controls

Sunday, December 16th, 2012

I don’t usually do serious topics on this blog, partly because that’s not the kind of thing I usually consider myself able to comment on with any real knowledge but mostly because I’m only pretending to be an adult and worry that, by trying to comment on such weighty matters, I’ll reveal my true nature. But I’m going to make an exception having read on the ORG website that the Department for Education have stopped plans to put a default-to-enabled parental filter in place on all UK internet connections. I feel, as someone who has a “day job” in the education sector and two teenagers rattling around the house, that this decision was very sensible of the DfE’s part and, for what it’s worth, applaud them for it.

That might sound counterintuitive but I’ve learnt a few things from spending some eight years working behind filtering and far longer on the internet at large; firstly, you can throw up the best possible protection and, if a bright child wants to see something they shouldn’t, the chances are that they’ll still find a way to do so before explaining what they did to their friends. I’ve seen some truly impressive work-arounds from pre-teen children to reach content on the internet that was thought to be inaccessible through local filtering service Leeds Learning Network and in those situations I’m a little torn; I know my job and have to arrange for the hole to be plugged as securely as possible, but part of me really appreciates the ingenuity involved in getting around the filter and has to bite it’s tongue about wanting to encourage that kind of out-of-the-box thinking.

The most important however is that filtering doesn’t really work, at least not with any level of reliability or consistency, so even the best laid plans can and do go severely astray. Take Grimes Dyke primary school whose name has repeatedly triggered false positives to the point where their own website, hosted by filtering provider LLN, has on occasion not been available to anyone using said filter. Yes it was a simple, faintly ridiculous mistake (as was the blocking of pages on another school website where the words “under construction” appeared because there had been a spate of proxies trying to pass themselves off in a similar way) but automated filters make those mistakes on a regular basis and sometimes without the issue being noticed for weeks on end. Scaling this sort of arrangement up to a national level was never going to alleviate that problem.

And all this is even before we worry about who actually manages a nationwide internet blacklist; do we give control of what we see over to the government and, if so, how do we know they can be trusted not to abuse that power because it presumably wouldn’t take much for a Tory MP to “accidentally” add parts of the Labour party’s website to filtering for example. And, as I said, someone clever can always figure out a way of “gaming” the protection and, if a pre-teen child can inventively work their way around a reasonably heavy grade internet filter, a crowd sourced” interest group” has pretty good odds of getting what they consider to be an objectionable website blocked.

The Daily Mail were extremely vocal in the campaign for this bill, with shock headlines on their website screaming “four in 10 parents say their children have been exposed to internet porn” and heading up articles that drew attention away from the point that those aforementioned parents should’ve been watching what their kids were doing online. Because, ultimately, that’s whose responsibility it is to protect your children on the internet and, if you haven’t been bothered to put at least a little time into researching possible options to filter your own connection, you are far more responsible than your service provider, the government or even the pornographers for your child seeing something inappropriate. A good starting point is Get Safe Online which provides advice on setting up parental controls and safeguarding your children (or indeed yourself) online.

We now return you to our scheduled programming.

Mmm, Raspberry Pi!

Thursday, May 31st, 2012

It took a while, but my shiny new Raspberry Pi arrived yestarday… so I’ve just picked it up from the sorting office, plugged in a spare keyboard and mouse through a Poundland hub, run a cable to our old JVC CRT telly, inserted the 4Gb SD card I’d prepped with Debian Squeeze and powered it on… and away it went!

RasPi

In fact it worked so well that, although the photo was uploaded from my (t)rusty old laptop, this blog posting is being written via the Pi itself!

Of course the big question right now is what to actually do with the thing now i’ve got it… there’s a dead 48K Spectrum knocking about that I got specifically but how to mount it and how to persuade the Pi to natter with it’s keyboard…?