Virus writers have developed a 'Peeping Tom' worm that can use webcams to spy on computer users in their home or workplace, internet security watchers have warned.

The newly discovered Rbot-GR worm (W32/Rbot-GR) spreads via network shares, exploiting a number of Microsoft security vulnerabilities before installing a backdoor Trojan as it travels, security firm Sophos said.

The company added that, once the worm infects a computer, remote hackers can easily gain access to the information on the PC's hard drive and steal passwords, as well as spy on innocent users via their webcam and microphone.

"More and more hackers are interested in spying on the people they manage to infect with their worms and Trojan horses," said Graham Cluley, senior technology consultant for Sophos, in a statement.

"In the workplace, this worm opens up the possibilities of industrial espionage. At home it is equivalent to a Peeping Tom who invades your privacy by peering through your curtains.

"If your computer is infected and you have a webcam plugged in, then everything you do in front of the computer can be seen, and everything you say can be recorded."

According to Sophos, the W32/Rbot-GR worm is evidence of a growing trend of malware spying on innocent home computer owners and poorly protected businesses.

"With many home users keeping poorly defended PCs in their bedroom, there is considerable potential for abuse," added Cluley.

"The message is simple: keep your PC protected against the latest threats with antivirus software and firewalls, and if in any doubt unplug your webcam when you're not using it."

More information on the worm and instructions on how to remove it are available from Sophos here.