Safari users have been advised to update their browser to the newest version after Apple revealed the numerous security holes that Safari 5 and 4.1 have filled.
In a security advisory, Apple pointed to 48 threats that hackers could exploit if users leave the vulnerabilities unpatched.
By updating to Safari 5 or Safari 4.1, users can avoid getting hit by an attacker taking advantage of security holes in older browsers, according to Apple.
Safari 5 requires Mac OS X Leopard 10.5.8 or Mac OS X Snow Leopard 10.6.2 or later, meaning those with older operating systems will need to get Safari 4.1 to avoid any potential problems.
Furthermore, Safari 5 is not available on systems predating Windows XP SP2, Windows Vista or Windows 7.
Those who use browsers with weaknesses could be hit by unexpected application termination or arbitrary code execution when visiting a malicious website, among other threats.
"It doesn't matter whether you own a Mac or a Windows PC, if you run Safari the message is clear. Update your browser and ensure that you are protected against hackers exploiting the security holes detailed in the security advisory on Apple's website," said Graham Cluley, senior security consultant at Sophos, in a blog post.
"Safari users should practise safe computing, and update their systems as soon as possible," Cluley added, warning of the "swarm of security vulnerabilities" affecting older versions of the browser.
Apple launched Safari 5 on the same day as the Cupertino company introduced iPhone 4 and the browser is available for download now.
