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Version 3.9.15

On 11 Jan, 2017, WordPress 3.9.15 was released to the public.

See also: other WordPress Versions.

Installation/Update Information

To download WordPress 3.9.15, 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 WordPress 4.7.1 release post: WordPress versions 4.7 and earlier are affected by seven security issues:

  1. Remote code execution (RCE) in PHPMailer – No specific issue appears to affect WordPress or any of the major plugins we investigated but, out of an abundance of caution, we updated PHPMailer in this release. This issue was reported to PHPMailer by Dawid Golunski and Paul Buonopane.
  2. Cross-site scripting (XSS) via the plugin name or version header on update-core.php. Reported by Dominik Schilling of the WordPress Security Team.
  3. Cross-site request forgery (CSRF) bypass via uploading a Flash file. Reported by Abdullah Hussam.
  4. Cross-site scripting (XSS) via theme name fallback. Reported by Mehmet Ince.
  5. Post via email checks mail.example.com if default settings aren’t changed. Reported by John Blackbourn of the WordPress Security Team.
  6. A cross-site request forgery (CSRF) was discovered in the accessibility mode of widget editing. Reported by Ronnie Skansing.
  7. Weak cryptographic security for multisite activation key. Reported by Jack.

List of Files Revised

wp-includes/class-wp-theme.php
wp-includes/ms-functions.php
wp-includes/functions.php
wp-includes/class-phpmailer.php
wp-includes/version.php
wp-includes/class-smtp.php
wp-mail.php
license.txt
readme.html
wp-admin/includes/screen.php
wp-admin/includes/media.php
wp-admin/widgets.php
wp-admin/update-core.php
wp-admin/about.php