Nearly a quarter of all web users have failed to update their web browser, according to a new study from anti-virus firm Kaspersky Lab.
According to the study, Firefox users are the most likely to be using old software. Internet Explorer (IE) users, meanwhile, were reported to be the most likely to be using up to date browser.
"Our new research paints an alarming picture. While most users make a switch to the most recent browser within a month of the update, there will still be around a quarter of users who have not made the transition," said Kaspersky director of whitelisting and cloud infrastructure research Andrey Efremov.
"That means millions of potentially vulnerable machines, constantly attacked using new and well-known web-born threats. This is strong evidence of the urgent need for proper security software which is able to react to new threats in a matter of minutes, not days or even weeks."
Kaspersky surveyed the browsers of users on its Kaspersky Security Network to come up with its results. The Kaspersky Security Network is an optional program for Kaspersky users that tracks consumers security habits in real-time.
The company's research found that Microsoft's IE browser was the most commonly used browser with a 37.8 percent market share. Google's Chrome browser came in a close second with a 36.5 percent share of the browser market.
Mozilla's Firefox and the Opera browser rounded out the top four most used browsers. According to Kaspersky's numbers, 19.5 percent of surveyed users were running the Firefox browser and six percent of users were using Opera.
Firefox was reported to be the browser least likely to see updates, according to Kaspersky. The Mozilla browser was shown to be up to date on just over 66 percent of surveyed computers. That's compared to the 80.2 percent of computers running the most up to date version of IE.
Opera and Chrome browsers also saw many of its users update. 79.2 percent of Chrome users were running the latest version of Google's browser. While 78.1 percent of Opera users were reported to be up to date.
In total Kaspersky found that as many as one in 10 web users were running on outdated browsing software.
A main issue for some was that if a user was running Windows XP they wouldn't be able to update to the latest IE browser. That fact could have been why 3.9 percent of IE users were still running the obsolete IE 6 and 7 browsers which no longer receive security updates.
Kaspersky recommends XP users replace IE with an alternative browser to get the most out of their security.