Index: wp-comments-post.php
===================================================================
--- wp-comments-post.php	(revision 7627)
+++ wp-comments-post.php	(working copy)
@@ -11,7 +11,7 @@
 
 $comment_post_ID = (int) $_POST['comment_post_ID'];
 
-$status = $wpdb->get_row("SELECT post_status, comment_status FROM $wpdb->posts WHERE ID = '$comment_post_ID'");
+$status = $wpdb->get_row( $wpdb->prepare("SELECT post_status, comment_status FROM $wpdb->posts WHERE ID = %d", $comment_post_ID) );
 
 if ( empty($status->comment_status) ) {
 	do_action('comment_id_not_found', $comment_post_ID);
Index: wp-includes/taxonomy.php
===================================================================
--- wp-includes/taxonomy.php	(revision 7627)
+++ wp-includes/taxonomy.php	(working copy)
@@ -749,7 +749,7 @@
 	}
 
 	if ( !empty($taxonomy) )
-		return $wpdb->get_row("SELECT tt.term_id, tt.term_taxonomy_id FROM $wpdb->terms AS t INNER JOIN $wpdb->term_taxonomy as tt ON tt.term_id = t.term_id WHERE $where AND tt.taxonomy = '$taxonomy'", ARRAY_A);
+		return $wpdb->get_row( $wpdb->prepare("SELECT tt.term_id, tt.term_taxonomy_id FROM $wpdb->terms AS t INNER JOIN $wpdb->term_taxonomy as tt ON tt.term_id = t.term_id WHERE $where AND tt.taxonomy = %s", $taxonomy), ARRAY_A);
 
 	return $wpdb->get_var("SELECT term_id FROM $wpdb->terms as t WHERE $where");
 }
@@ -888,8 +888,7 @@
 	if ( $ignore_empty )
 		$where = 'AND count > 0';
 
-	$taxonomy = $wpdb->escape( $taxonomy );
-	return $wpdb->get_var("SELECT COUNT(*) FROM $wpdb->term_taxonomy WHERE taxonomy = '$taxonomy' $where");
+	return $wpdb->get_var( $wpdb->prepare("SELECT COUNT(*) FROM $wpdb->term_taxonomy WHERE taxonomy = %s $where", $taxonomy) );
 }
 
 /**
@@ -918,7 +917,7 @@
 	foreach ( $taxonomies as $taxonomy ) {
 		$terms = wp_get_object_terms($object_id, $taxonomy, 'fields=tt_ids');
 		$in_terms = "'" . implode("', '", $terms) . "'";
-		$wpdb->query("DELETE FROM $wpdb->term_relationships WHERE object_id = '$object_id' AND term_taxonomy_id IN ($in_terms)");
+		$wpdb->query( $wpdb->prepare("DELETE FROM $wpdb->term_relationships WHERE object_id = %d AND term_taxonomy_id IN ($in_terms)", $object_id) );
 		wp_update_term_count($terms, $taxonomy);
 	}
 }
@@ -1293,7 +1292,7 @@
 		$delete_terms = array_diff($old_terms, $tt_ids);
 		if ( $delete_terms ) {
 			$in_delete_terms = "'" . implode("', '", $delete_terms) . "'";
-			$wpdb->query("DELETE FROM $wpdb->term_relationships WHERE object_id = '$object_id' AND term_taxonomy_id IN ($in_delete_terms)");
+			$wpdb->query( $wpdb->prepare("DELETE FROM $wpdb->term_relationships WHERE object_id = %d AND term_taxonomy_id IN ($in_delete_terms)", $object_id) );
 			wp_update_term_count($delete_terms, $taxonomy);
 		}
 	}