Web users heading to chat rooms to find love online in the run up to Valentine's Day are being warned about the re-appearance of 'flirt bots'.

Security vendor PC Tools revealed it had identified programs that strike up a conversation with web users and then send them links to malicious websites. These site then aim to obtain credit card details, passwords and logins to a number of different online sites, or even convince users to purchase fake antivirus software.

The botnets are called 'flirt bots' because of the saucy nature of the conversation that takes place.

The flirt bot PC Tools identified targets MSN chat rooms

PC Tools said it was the first flirt bot the security firm had seen since the 'Cyberlover' in 2007.

"It seems that the intelligence behind these types of attacks has moved on significantly in this time. The software is now smart enough to tailor its responses to your answers and will be harder for even the more digitally active user to identify and therefore avoid," said PC Tools spokesperson Richard Clooke.

Clooke added that the specific bot PC Tools had discovered was exploiting the MSN chat forums, "but generally it could be targeting any type of chat forum in order to make contact".

"We believe Flirt Bot is taking particular advantage of the seasonal interaction of people in chat rooms in the run up to Valentine's day."

PC Tools urged web users not to click on links received through instant messages or in chat rooms and ensure security software is up to date.

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