A new version has been released for Firefox 2 and Firefox 3. The version number of the former is 2.0.16 while 3.0.1 is the version of the later.

As the article in The Register notes, 2.0.0.16 fixes vulnerabilities in its CSS reference counter and it also fix a flaw that allows multiple tabs to be launched in Firefox while the program is not open.

3.0.1 fixes the same bugs that are described above. It also included a fix for malformed GIF files. This version came out yesterday but the other version (2.0.0.16) was released a day earlier. Mozilla will stop the support on version 2 by mid-December according to The Register.

Source: The Register