Version 18.104.22.168 is available here. It fixes some security vulerabilities rated Highly Critical, so check your version, and update if it's not 22.214.171.124.
It's never a bad time to check for updates on other "Internet-facing" software like media players (WinAmp, iTunes, QuickTime), other browsers, and instant-messaging programs, either. Windows users can hit Windows Update to see if they need any new updates for the OS and its built-in stuff, and Mac users can use Apple's Software Update feature.
I've met Windows users who think that because they use a different browser than Internet Explorer, they don't need to go to Windows Update, or at least that they don't need to keep Internet Explorer patched. Not so. Visit the Windows Update site monthly, and/or turn on Automatic Updates in the Control Panel, so you keep your vulnerabilities to a minimum
Also, if you have an old-generation antivirus software that was made several years ago, it's probably not fully equipped to handle new types of threats like we have today. If you can't afford a new pay-for version, consider using a free-for-home-users one like AntiVir, which is probably the best of the free ones. mech's general antivirus configuration tips