WordPress Release: 3.1.1

TL;DR

WordPress 3.1.1 is a maintenance and security release that addresses numerous bugs and issues from the 3.1 release. This update focuses on fixing security vulnerabilities, improving permalink handling for custom post types and taxonomies, enhancing admin bar functionality, and resolving various UI and compatibility issues. It's an important update for all WordPress 3.1 users that improves stability and security without introducing new features.

Highlight of the Release

• Enhanced security with additional nonce checks in uploaders
• Fixed permalink handling for custom post types and taxonomies
• Improved admin bar functionality and appearance
• Better error handling for database connections during installation
• Fixed issues with taxonomy queries and term handling

Migration Guide

No specific migration steps are required for this maintenance release. Simply update your WordPress installation to version 3.1.1 through the WordPress admin dashboard or by downloading the update from wordpress.org.

Upgrade Recommendations

This update is highly recommended for all WordPress 3.1 users as it contains important security fixes and resolves numerous bugs that could affect site functionality. The update is backward compatible and should not cause any issues with existing themes or plugins.

Bug Fixes

• Fixed permalink handling for custom post types and taxonomies with with_front=false
• Resolved issues with taxonomy queries for single post requests
• Fixed plugin header parsing to be more liberal (like in 3.0), allowing PHPdoc style headers
• Corrected handling of oversized custom user/site icons in the admin bar
• Fixed position of submenus when showing avatar in admin bar
• Resolved discrepancy in the nested loop in the Recent Comments dashboard widget
• Fixed issues with post format handling, including not querying post format for post types that don't support formats
• Prevented double index.php prepend on PATHINFO custom taxonomy permalinks
• Fixed canonical redirects to avoid redirect loops on some IIS setups
• Resolved issues with search query handling to avoid mangling the current site path variable
• Fixed error in comments bubble display method
• Added back compatibility fields to queried category objects
• Restored category permalink behavior from WordPress 3.0 and earlier
• Fixed variable name conflict in _get_meta_sql()
• Improved error handling during database connection failures in installation
• Prevented canonical redirects for custom rewrite rules for taxonomies

New Features

No new features were introduced in this maintenance release. WordPress 3.1.1 focuses entirely on bug fixes, security improvements, and resolving issues from the 3.1 release.

Security Updates

• Added nonce checks to uploaders for improved security
• Improved sanitization and escaping throughout the codebase
• Removed unused/non-functional code with old-style CSRF checking
• Enhanced security for media item fetches with capability and type checks
• Improved handling of post status, comment status, and ping status with proper sanitization
• Better escaping for translations into attributes
• Proper URL escaping in admin functions

Performance Improvements

• Reduced backtracking in make_clickable() regex
• Reduced PCRE recursion limit to avoid segfaulting
• Improved taxonomy query handling by not performing taxonomy queries for single post requests
• Better handling of query variables to avoid unnecessary processing

Impact Summary

WordPress 3.1.1 is a maintenance release that significantly improves the stability and security of WordPress 3.1. It addresses several security vulnerabilities by adding nonce checks to uploaders and improving sanitization throughout the codebase. The update also fixes numerous bugs related to permalinks, taxonomy queries, and admin functionality.

For developers, this release resolves issues with custom post types and taxonomies, improves error handling, and adds a new hook for login script enqueuing. Site administrators will benefit from fixed user management functionality and improved admin bar display. Content creators will experience better handling of post formats, titles, and media.

This update maintains backward compatibility while addressing critical issues, making it an essential upgrade for all WordPress 3.1 users. No new features are introduced, keeping the focus on stability and security improvements.