The Wireless Ghost


The Wireless Ghost

In the fifth of a new weekly series for Cambridge Network members, IT governance expert Alan Calder explains the ABCs of business security and compliance. This week he looks at uninvited intruders on wireless networks (or WLANs).

The Problem

Your business information is only as secure as your weakest link.

When you set up a network so that anyone can log onto it, without even needing to plug in, well – then anyone CAN log onto it. In truth, anyone even minimally competent at basic DIY can set up a WLAN in as long as it takes to plug in a few wireless cards and run some simple software. There’s nothing to it – and that’s because wireless equipment all ships with its default security settings at ZERO.

It’s equally simple to buy some software off the Internet that will enable a hacker to find ‘open’ WLANs (‘war driving’). It’s as easy for an employee to plug a wireless access point into a fixed network as it is for him to bring an insecure wireless PC into the office (or, more terrifyingly, a branch office) and uses it to connect to the secure office network.

Any one of these three scenarios – an ‘open’ WLAN, a rogue access point or a rogue user – opens your network to the Wireless Ghost.

The Risks

The ‘war driver’, who also has a wireless computer, can hack into your network via any of these options – through your unsecured access point, through the rogue access point, or by piggybacking on the rogue machine’s access.

The first scenario may still leave the hacker with the problem of getting past your firewall but, in the other two, he’s straight past it from the word go. And that means he’s lose on your network, able to access ALL your confidential data, able to destroy and corrupt data to his heart’s content, able to set your network up for a more severe attack at another time. And you won’t know he’s there until it’s way too late.

The Impacts

A wireless ghost on your network can steal confidential information, release viruses, worms, Trojans and other malware, and use your systems for denial of service and other network attacks

And confidential corporate is subject to data protection, human rights and privacy legislation – as well as being valuable to its owners.

What do we do about it?

The critical steps are:

1. Securing your WLAN – which means deploying enterprise-level security policies (including encryption and authentication) and security architectures.

2. Taking action against rogue access points – set your own ‘war drivers’ loose!

3. Take action against rogue users – deploy network monitoring and remote device control software that catches the culprits.

What else?

Once you’ve got a secure WLAN, with wireless access only permitted through a secure VPN, your only real danger arises when someone loses – or has stolen – a notebook computer that’s all set up for authenticated access to your network.

        As usual, it’s a combination of technology, procedure, staff training and luck that have to combine to keep ghosts out of the machine.

Next week: Voice insecurity

Alan Calder’s company provides businesses with consultancy support and advice on governance and business security. Visit, e-mail or telephone + 44 845 070 1750

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