BOOT CAMP 294 (30/09/03)

Paranoia part 2

In last week’s Boot Camp we looked at the way Windows automatically records the address of every website you visit and hides it away in secret protected files but that’s far from being the only threat to your privacy. It’s quite possible that right now your PC is sending out information about your web surfing activities, maybe even details of your on-line bank accounts, passwords, PINs, credit card numbers and any other personal or private data stored on your computer.

There are many ways PCs can violate your privacy the best known being ‘cookies’. These are small text files that are automatically downloaded onto your PC when you access web sites. On the face of it cookies appear fairly harmless and they are designed to store things like passwords for web sites that you visit regularly, to help speed up login, or personalising content according to your preferences. However, they can have other applications including collecting demographic data for companies selling advertising on the web and sufficient information can be stored in cookies to create a profile of your web activities and even reveal your identity to anyone with access to your PC, or the wherewithal to extract information from it.

To be fair most cookies are benign but if you want to take charge of what’s being stored on your PC you should review your browser’s cookie handling settings. In Internet Explorer and its derivatives go to Internet Options on the Tools menu select the Privacy tab then click the Advanced button. The default setting is usually ‘Automatic’ but you can easily override this and either block all cookies, or tell the browser to ‘Prompt’ before downloading. Unless you routinely visit a lot of sites requiring passwords or logins you should enable the ‘Allow Session cookies’ option; this gives permission for cookies to be stored but they are deleted when the browser is closed. This is a far from perfect method the pop-up ‘Prompt’ dialogue box can become tiresome but at least you are in control. For a more sophisticated solution see Tip of the Week.

Cookies are short strings of text and cannot be used to carry viruses or malicious code but there are plenty of other nasties lurking inside web pages, emails, files and programs that you may unwittingly allow onto your computer. Adware, Homepage Hijackers, Spyware and Trojans are programs, stealthily installed on your PC, usually without your knowledge, that use your Internet connection – without your permission – to transmit data to whoever planted it. Adware and Homepage Hijackers are mostly just annoying and are often responsible for adverts popping up on your screen, or changing your homepage. Spyware is more insidious and operates in the background, sending data from your PC and possibly opening it up to attack but the most worrying threat comes from Trojans, which are specifically designed to steal data or corrupt your PC’s operating system.

Fortunately there is much you can do to minimise the risk of both your computer sending out information, and preventing these programs being installed in the first place. The first step is to install a Firewall. This is a program that constantly monitors your PC’s Internet connection, alerting you to any attempts to hack into your PC from outside and any programs on your PC trying to access the Internet, and this is absolutely essential if you are using a broadband or ‘always’ on Internet connection. Incidentally, Windows XP has a built-in firewall but this only prevents external infiltration and does nothing to stop outgoing connections.

There are plenty of good commercial firewalls available but there are two excellent freeware programs, namely ZoneAlarm (www.zonelabs.com) and the more sophisticated Agnitum Outpost (http://www.agnitum.com/products/outpost/), which both provide a good level of basic protection, though you might want to investigate the more advanced paid-for versions which provide increased flexibility and even better security.

Removing Adware, Spyware Hijacker and Trojan programs is very easy and to date we have recommended two freeware programs, namely Adaware (www.lavasoft.com) and Spybot Search and Destroy (http://www.safer-networking.org/). However, I have noticed that for the past week or two Adaware has not been issuing any new signature files so I suggest that for the time being you stick with Spybot. After installing the program click the Update button to download the latest signatures then get into the habit of carrying out a full scan of your computer at least once a week.

Next week – Paranoia, part 3

JARGON FILTER

FREEWARE

Shareware programs that are free to use, but the author retains control and copyright over the original programming code. N.B. some freeware and shareware programs may contain advertising messages and/or adware and spyware programs 

HACKING

Any attempt to access files on your PC, usually through an open or unprotected Internet or network connection

SIGNATURE FILE

Samples of computer code used to identify viruses, worms, spyware and Trojan programs

TIP OF THE WEEK

The cookie management utilities in most browsers tends to be fairly basic but this little freeware program, called Cookie Monster, gives you much greater control. You can display the information contained in the cookies, quickly delete the ones you don’t want, and preserve the useful ones, containing login details or personal preferences of your favourite web sites. Cookie Monster works on all popular browsers (Internet Explorer, Netscape, Mozilla etc.) and supports Windows 95/98/ME/NT/2Kand XP, you’ll find the zipped download (238kb or installer (276kb) at: http://www.ampsoft.net/