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Version 4.0.1

On November 21, 2014, WordPress 4.0.1 was released to the public. This is a security update for all previous WordPress versions.

Installation/Update Information

To download WordPress 4.0.1, update automatically from the Dashboard > Updates menu in your site's admin area or visit https://wordpress.org/download/release-archive/.

For step-by-step instructions on installing and updating WordPress:

If you are new to WordPress, we recommend that you begin with the following:

Summary

From the announcement post:

  • Three cross-site scripting issues that a contributor or author could use to compromise a site.
  • A cross-site request forgery that could be used to trick a user into changing their password.
  • An issue that could lead to a denial of service when passwords are checked.
  • Additional protections for server-side request forgery attacks when WordPress makes HTTP requests.
  • An extremely unlikely hash collision could allow a user’s account to be compromised, that also required that they haven’t logged in since 2008 (I wish I were kidding).
  • WordPress now invalidates the links in a password reset email if the user remembers their password, logs in, and changes their email address.

List of Files Revised

readme.html
wp-admin/about.php
wp-admin/includes/class-wp-plugin-install-list-table.php
wp-admin/includes/image.php
wp-admin/includes/plugin-install.php
wp-admin/includes/post.php
wp-admin/js/editor-expand.js
wp-admin/js/editor-expand.min.js
wp-admin/js/media.js
wp-admin/js/media.min.js
wp-admin/plugin-install.php
wp-admin/press-this.php
wp-admin/upload.php
wp-includes/canonical.php
wp-includes/class-phpass.php
wp-includes/css/media-views-rtl.css
wp-includes/css/media-views-rtl.min.css
wp-includes/css/media-views.css
wp-includes/css/media-views.min.css
wp-includes/formatting.php
wp-includes/http.php
wp-includes/js/media-grid.js
wp-includes/js/media-grid.min.js
wp-includes/js/media-views.js
wp-includes/js/media-views.min.js
wp-includes/js/mediaelement/flashmediaelement.swf
wp-includes/js/mediaelement/mediaelement-and-player.min.js
wp-includes/js/quicktags.js
wp-includes/js/quicktags.min.js
wp-includes/js/tinymce/plugins/wpeditimage/plugin.js
wp-includes/js/tinymce/plugins/wpeditimage/plugin.min.js
wp-includes/js/tinymce/plugins/wpview/plugin.js
wp-includes/js/tinymce/plugins/wpview/plugin.min.js
wp-includes/js/tinymce/wp-tinymce.js.gz
wp-includes/kses.php
wp-includes/link-template.php
wp-includes/media-template.php
wp-includes/media.php
wp-includes/ms-functions.php
wp-includes/pluggable.php
wp-includes/post.php
wp-includes/session.php
wp-includes/user.php
wp-includes/version.php
wp-login.php
See also: other WordPress Versions.