Although this has been issues for Firefox, it is virtually the same for any browser, or any updates, if you don't know where you are getting them from, then you can be in a heap of trouble...
Unlike the previous Chrome bug, this problem isn't with Firefox itself. Instead, hackers are advertising links on the Internet to download Firefox.
The problem is that the version of Firefox, while appearing to be legitimate, is actually loaded with adware extensions.
The hackers use compromised websites to display a warning telling you that your version of Firefox is out of date (regardless of what version you are actually using) and prompting you to download an updated version.
If you do so, you end up with the malware infected version of Firefox on your system.
Christopher Boyd, a senior threat researcher at ThreatTrack Security, says: "The browser build appears to be genuine, however it has been compromised with a multitude of add-ons, adware, toolbars and other malicious and irritating accompaniments that will find their way onto the user’s PC as part of the install".
Not only will the unwanted add-ons pop up adverts while you are browsing the web, they'll also litter your desktop with shortcut icons and seriously slow down your PC.
This is a classic Trojan tactic: hiding malware inside legitimate software. The problem is that the add-on extensions supported by all web browsers, not just Firefox, make this kind of attack easy.
The solution is to only ever download Firefox from legitimate locations. The best place is the main Mozilla website, although you may already have other safe sites:
http://www.mozilla.org/en-US/
The real version of Firefox will never come packed with malware infections and is quite safe. And, if you have Firefox installed on your system already, it will be configured to automatically update itself when a new version becomes available, so you don't need to download updated versions.
I guess the hackers are moving on from the IE or rather adding the other browsers in addition to still plaguing IE, as they become more popular.... Damn hackers, should be the death penalty for them...