Firefox is the open source web browser, part of the Mozilla project. Immensely popular (over 50 million downloads so far) and one of its claims to fame is that being a different set of code from internet Explorer, it was immune to the various nasties that attack browsers (browser hijack, mal-ware, malicious pop-ups, zombie takeovers, etc...) Here is a website that offers information on what may be the first known vulnerabilities to Firefox.
Firefox Vulnerabilities: The Official Word
Mozilla acknowledged that there are flaws in Firefox that can make things uncomfortable for the users of the open-source browser.
Although there have been no reports of systems falling victim because of the vulnerabilities, the potential for cross-site scripting attacks prompted Secunia to slap an "extremely critical" rating on the bugs. Web surfers this weekend got a taste of how damaging a successful attack can be to with a proof of concept as well as the release of exploit code by the Greyhats Security Group, according to an InternetNews report.
Today, Mozilla posted a security advisory summarizing the nature of the flaws as well as ways to cut the chances of an unfortunate run-in with a maliciously coded website.
The website gives a link to a dummy malicious website that you can use to test your copy of Firefox. Overall, Firefox is a great browser -- there are a few things that it would not do so I am still sticking with IE for the moment but I am looking at it with each new version. Opera is an alternative browser to check out too -- commercial but worth a look...