[top photo: Janice Lim, a Nanyang Polytechnic part-time lecturer who had her work on her laptop almost wiped out following a malware attack from a student's USB drive.]

By Tan Chong Yaw

ONE exception was all it took for an unidentified malware to erase more than 30 files - over a year's work - from her laptop.

Janice Lim, 34, a part-time communication skills lecturer at Nanyang Polytechnic, does not usually allow her students to insert their USB flash drives into her laptop.

In May this year, she made an exception: She let one of her foreign students do so during a tutorial, as the student had forgotten to take her own laptop to make her presentation. It was a mistake.

'I panicked. I thought all my hard work was gone,' recalls Janice.

Only after the incident did she realise that her antivirus software had expired last year.

Fortunately for Janice, the last time she backed up her files was a fortnight before the incident. Still, she spent three days recreating the files that had not been archived since the last backup.

Malware - malicious software designed to sneak into and damage your PC - can take more forms than the shape-shifting villain Mystique in the X-Men movies and be as deadly.

David Freer, Symantec Asia-Pacific and Japan vice-president for consumer business lists the top five signs that your PC has been attacked:

• It slows down a lot or crashes when launching applications. Or, applications load slower and do not work properly.
  
  
• Unusual and random error messages appear.
  
  
• New files appear on your hard drive - without your installing any new programs.
  
  
• Pull-down menus look different from what you are familiar with.
  
  
• The antivirus software is disabled for no apparent reason.

'The Web is now the primary vector for infection,' warns David.

Sopho's technology head Paul Ducklin points to visible signs of infection when you are browsing - like mushrooming pop-ups, changes to your home page or bookmarks, slow browsing or crashes and frequent rerouting to other websites.

David cautioned, however, that sophisticated malware is stealthy. Attackers now gun for financial gain, not fame. Their prize is personal information like bank, Facebook, Twitter and e-mail account details.

Fortinet's security expert Guillaume Lovet says: 'For cyber-criminals, an infected computer equals cash.'

Fort Knox measures are not necessary. Just ensure that your antivirus software is up-to-date.

McAfee's Hong Kong-based security expert Vu Nguyen scans his PC once every two to three days.

Apply common sense to avoid malware, adds David. He recommends doing the following:

• Open the attachments from only someone you know.
  
  
• Delete suspect e-mail messages without even opening them.
  
  
• If an online chat buddy appears to be sending you strange messages, files or links, stop the chat session.
  
  
• Be paranoid of requests asking you to divulge your bank account name and password.
  
  
• After clicking on a link to go to a website, check the browser address line. For instance, twitter.com should not read twitters.com.
  
  

This article was first published in The Straits Times.

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