Security companies are notorious for sending out well-timed warnings that tap into the latest hot topic in a bid to promote the benefits of their products.

Every Christmas, New Year, Valentines Day and Easter is preceded by countless press releases warning us not to click on an apparently innocent seasonal email. Even big events such as last summer’s World Cup were accompanied by threats that unscrupulous hackers would attempt to take over people’s PCs by offering a link of a ‘live feed’ of the big match.

But the latest warning surely wins the award for the most opportunistic (and tenuous) security warning in history. Want to know the next threat to business IT security? The ban on smoking in the workplace.

NTA Monitor contends that businesses will leave themselves liable to attack by leaving the back door open so that smokers can sneak out for a crafty cigarette. The security consultancy claims its recent social-engineering test – in which a ‘researcher’ snuck in through an open door and then gained access to a company’s network unchallenged – shows that efforts to accommodate smokers could cause mayhem in the IT room.

"It used to be that companies 'left the back door open' in terms of internet security. Now they are literally leaving their buildings open to accommodate smokers,” said Roy Hills, technical director at NTA Monitor.