Updates should be pushed in the next 24 hours but if you want it right now, select Check for Updates… in Firefox’s Help menu. If you need the full Firefox 2 download, check Mozilla’s old versions page.
Remember that Firefox 3 is the current version and according to Mozilla support policies, the Firefox 2 branch will get updates until around mid-December, six months after the current version release.
It should be noted that none of these vulnerabilities are present in Firefox 3. Nine of them were already fixed before final release and three of them don’t affect it because of changes to how related features internally work (page reflow, certificate handling and file uploading).
Firefox 3 is already on its own maintenance cycle with the first update, Firefox 3.0.1 (Mozilla has changed to three digit versioning with Firefox 3), targeted for mid-July, most likely to coincide with another Firefox 2 update.