The latest build in the FF 2 series was released yesterday. According to the release notes this release fixes several critical vulnerabilities besides the more obvious bug fixes.
Critical
- MFSA 2007-23 Remote code execution by launching Firefox from Internet Explorer
- MFSA 2007-21 Privilege escallation using an event handler attached to an element not in the document
- MFSA 2007-18 Crashes with evidence of memory corruption
High
- MFSA 2007-24 Unauthorized access to wyciwyg:// documents
- MFSA 2007-19 XSS using addEventListener and setTimeout
If you haven’t updated/upgraded already visit the Firefox 2 download page immediately.