Britain is once again 'top of the bots' with the world's highest proportion of known bot-infected computers. In the first half of 2005, The UK has almost a third (32 per cent) of all bots – virus-infected, zombie PCs under the control of hackers and used for malicious purposes such as identity theft and spam distribution –. Britain also topped the chart in the second half of last year with a lower 26 per cent rating.

The statistics, taken from Symantec’s Global Internet Threat Report for the period January to June 2005, are based on the number of PCs worldwide that are known to be infected with bot agents, such as the infamous Agobot worm. Bot network activity has increased from below 5,000 bots per day in December 2004 to an average of 10,352 during this reporting period.

Symantec reckons the likely cause of this rise is down to the rapid growth in broadband subscriptions and the delayed download of software patches for operating systems and software.

Bots (short for ‘robots’) are programs that are covertly installed on a user’s computer in order to allow unauthorised users to control the infected computer remotely. Bot-infected computers are blamed for the rapid growth in phishing, spam, denial of service (DoS) attacks and other security risks such as spyware and adware. DoS attacks alone have risen by 680 per cent over the first half of 2005 to reach an average of 927 per day, according to Symantec. ®

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