A new study has shown that Firefox users are the most likely to have fully patched browsers and thus be safer online.

The 18-month study was conducted by researchers at the Swiss Computer Engineering and Networks Laboratory, along with IBM and Google.

Just over 83 per cent of Firefox users, 65.3 per cent of Safari users, 56.1 per cent of Opera users and 47.6 per cent of Internet Explorer users had fully patched browsers.

"For years the software industry has promoted one security best practice over all others: always use the most recent version of the installed software and instantly apply the latest patches," said the authors of the paper.

"With today's hostile internet and drive-by download attack vectors, failure to apply patches promptly or missing them entirely is a recipe for disaster, exposing the host to infection and possibly subsequent data disclosure or loss. "

Browser patching is becoming increasingly important as the majority of the internet malware currently in circulation enters systems via poorly patched browsers.

The research also found that IE users were the slowest to upgrade their browsers. Nineteen months after the release of IE7 barely half of IE users had upgraded (52.5 per cent) compared to 92.2 per cent of Firefox users.

The researchers recommend that software companies introduce automatic updating of browsers and should time stamp older browsers with a 'best before' date similar to the food industry.

The researchers also criticised Microsoft's monthly Patch Tuesday cycle approach.

"Microsoft's operating system auto-update functionality encompasses the IE update mechanism even if the browser is not in use," they said.

"But the fact that patch updates (for IE6 and 7) are typically only made available on a monthly basis means that updates are released less frequently (when compared to Firefox) which can result in lower short-term patching effectiveness."

The study also gave an up-to-date picture of browser market share. IE stands at 78 per cent, Firefox at 16 per cent, Safari at three per cent and Opera just 0.8 per cent.