Today WordPress has released 4.0.1 to fix critical security issues with previous versions. Multiple critical vulnerabilities have been discovered and fixed in several versions of WordPress Core including the current version 4.0.
WordPress versions 3.9.2 and earlier are affected by a critical cross-site scripting vulnerability, which could enable anonymous users to compromise a site. While this issue does not affect version 4.0, but version 4.0.1 does address these eight security issues:
- Three cross-site scripting issues that a contributor or author could use to compromise a site. Discovered by Jon Cave, Robert Chapin, and John Blackbourn of the WordPress security team.
- 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. Reported by Javier Nieto Arevalo and Andres Rojas Guerrero.
- Additional protections for server-side request forgery attacks when WordPress makes HTTP requests. Reported by Ben Bidner (vortfu).
- 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). Reported by David Anderson.
- WordPress now invalidates the links in a password reset email if the user remembers their password, logs in, and changes their email address. Reported separately by Momen Bassel, Tanoy Bose, and Bojan Slavković of ManageWP.
As of 10:00 AM today, all WordPress websites that I am maintaining now run WordPress 4.0.1