INTERNET users in Bahrain are being warned about greetings cards celebrating American Independence Day that can infect their computers with a virus.

The e-mail poses as a July 4 card sent by a friend only to infect the receiving computer with a trojan that can make it dependent on the author of the malware, a software designed to infiltrate or damage a computer system.

Experts say the subject lines of the e-mail are varied and are picked randomly from an embedded list, including Celebrate Your Independence, Fourth of July Party, God Bless America and Happy B-Day USA.

Once the victims click on the link to view the card they are taken to a bot computer hosting a trojan downloader named JS.Agent.kd.

A bot is a small application that can be downloaded innocently but is used by people who sell information to criminals for illegal activities.

The software can be used to co-ordinate a large automated attack on networked computers or to glean personal details from users.

A Batelco spokesman yesterday said he was, as yet, unaware of anyone who has become a victim of the scam, but warned people to be aware of the virus.

"As an Internet service provider we advise our customers to make sure not to open and preferably delete immediately any messages from unknown senders, specially those coming with attachments and make sure to have an up-to-date anti-virus software," he said.

"If you are not sure which one to use, just visit the site (www.download.com) and search for anti-virus software with a high rating and which can be used as shareware or freeware.

Experts say cyber criminals are frequently using special occasions such as New Year celebrations, Valentine's Day or countries' national days to send out viruses and because so many computer users send seasonal e-greetings, many of them unwittingly become victims.

Virus attacks are also becoming more sophisticated and have been exploiting breaking news stories from around the world in order to lure in potential victims.

To guard against masqueraded threats rely on intelligent and fast updating anti-virus software that catches viruses and worms at the entry point through which an external file comes into a computer.

Users who fall prey to the scam are advised to scan and clean their computers using the appropriate software.

geoff@gdn.com.bh