Junior sales staff are the most likely employees to cause technical security breaches, according to a study carried out in the UK and US.
The report by MessageLabs claimed that tech-savvy staff between the ages of 26 and 35, who use email, instant messaging, VoIP and the web without considering the potential dangers, constitute the biggest danger to businesses.
"A company's best assets and worst threats can be one and the same as the worst offenders are likely to be the best revenue generators," said Mark Sunner, chief security analyst at MessageLabs.
"Removing the culprits is obviously not an option. What should be removed is the ability to be a threat."
The most secure staff were middle management males between the ages of 26 and 35 who work within the technology department, according to the research.
However, companies are partly to blame for their staff's lack of caution, as just over 40 per cent of those surveyed fail to provide security training to staff.
"With almost half of all businesses not providing adequate training regarding online threats, employees are likely to be oblivious to the dangers and need protecting by other means," said Sunner.
The study also found that more than three quarters of respondents do not expect spam to cease being a problem.
The research was conducted by Vanson Bourne and questioned 942 IT decision makers across the US and UK during November and December 2006.
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