Ticket #11057: 11057.diff

wp-includes/canonical.php

@@ -125 +125 @@
                 } elseif ( is_year() && !empty($_GET['year']) ) {
                         if ( $redirect_url = get_year_link(get_query_var('year')) )
                                 $redirect['query'] = remove_query_arg('year', $redirect['query']);
-                } elseif ( is_category() && preg_match( '|^[0-9]+$|', $_GET['cat'] ) ) {
+                } elseif ( is_category() && !empty($_GET['cat']) && preg_match( '|^[0-9]+$|', $_GET['cat'] ) ) {
                         if ( $redirect_url = get_category_link(get_query_var('cat')) )
                                 $redirect['query'] = remove_query_arg('cat', $redirect['query']);
-                } elseif ( is_author() && preg_match( '|^[0-9]+$|', $_GET['author'] ) ) {
+                } elseif ( is_author() && !empty($_GET['author']) && preg_match( '|^[0-9]+$|', $_GET['author'] ) ) {
                         $author = get_userdata(get_query_var('author'));
                         if ( false !== $author && $redirect_url = get_author_posts_url($author->ID, $author->user_nicename) )
                                 $redirect['query'] = remove_query_arg('author', $redirect['author']);