WordPress 5.3.1 Security and Maintenance Release

WordPress 5.3.1 is now available!

This security and maintenance release features 46 fixes and enhancements. Plus, it adds a number of security fixes—see the list below.

WordPress 5.3.1 is a short-cycle maintenance release. The next major release will be version 5.4.

You can download WordPress 5.3.1 by clicking the button at the top of this page, or visit your Dashboard → Updates and click Update Now.

If you have sites that support automatic background updates, they’ve already started the update process.

Security updates

Four security issues affect WordPress versions 5.3 and earlier; version 5.3.1 fixes them, so you’ll want to upgrade. If you haven’t yet updated to 5.3, there are also updated versions of 5.0 and earlier that fix the security issues.

Props to Daniel Bachhuber for finding an issue where an unprivileged user could make a post sticky via the REST API.
Props to Simon Scannell of RIPS Technologies for finding and disclosing an issue where cross-site scripting (XSS) could be stored in well-crafted links.
Props to the WordPress.org Security Team for hardening wp_kses_bad_protocol() to ensure that it is aware of the named colon attribute.
Props to Nguyen The Duc for discovering a stored XSS vulnerability using block editor content.

Maintenance updates

Here are a few of the highlights:

Administration: improvements to admin form controls height and alignment standardization (see related dev note), dashboard widget links accessibility and alternate color scheme readability issues (see related dev note).
Block editor: fix Edge scrolling issues and intermittent JavaScript issues.
Bundled themes: add customizer option to show/hide author bio, replace JS based smooth scroll with CSS (see related dev note) and fix Instagram embed CSS.
Date/time: improve non-GMT dates calculation, fix date format output in specific languages and make get_permalink() more resilient against PHP timezone changes.
Embeds: remove CollegeHumor oEmbed provider as the service doesn’t exist anymore.
External libraries: update sodium_compat.
Site health: allow the remind interval for the admin email verification to be filtered.
Uploads: avoid thumbnails overwriting other uploads when filename matches, and exclude PNG images from scaling after upload.
Users: ensure administration email verification uses the user’s locale instead of the site locale.

For more information, browse the full list of changes on Trac or check out the version 5.3.1 HelpHub documentation page.