After nearly 15 million downloads since 3.4 was released not three months ago, the developers identified and fixed a number of bugs, including:
- Fix some issues with older browsers in the administration area.
- Fix an issue where a theme may not preview correctly, or its screenshot may not be displayed.
- Improve plugin compatibility with the visual editor.
- Address pagination problems with some category permalink structures.
- Avoid errors with both oEmbed providers and trackbacks.
- Prevent improperly sized header images from being uploaded.
The vulnerabilities included potential privilege escalation and a bug that affects multisite installs with untrusted users. These issues were discovered and fixed by the WordPress security team.