Get TikiWiki 2.4 here:
https://sourceforge.net/project/showfiles.php?group_id=64258&package_id=266122

changelog

More information on 2.0
http://doc.tikiwiki.org/TikiWiki+2.0
http://info.tikiwiki.org/art35

More information on 2.1
http://info.tikiwiki.org/art40

More information on 2.2
http://info.tikiwiki.org/art41

More information on 2.3
http://info.tikiwiki.org/art51

The security issue is addressed here:
http://secunia.com/advisories/34273/

As always, please report any security issues to security.tikiwiki.org


Work is ongoing on TikiWiki 3.0, which will be released in May 3rd, 2009. The main focus of version 3.0 will be further enhancements to the user interface, the admin interface, the theme system and built-in themes. Additional goodies include webservices and enhancements to the plugins.