Index: src/wp-includes/general-template.php
===================================================================
--- src/wp-includes/general-template.php	(revision 35090)
+++ src/wp-includes/general-template.php	(working copy)
@@ -2445,7 +2445,7 @@
  * @since 2.0.0
  */
 function rsd_link() {
-	echo '<link rel="EditURI" type="application/rsd+xml" title="RSD" href="' . get_bloginfo('wpurl') . "/xmlrpc.php?rsd\" />\n";
+	echo '<link rel="EditURI" type="application/rsd+xml" title="RSD" href="' . esc_url( site_url( 'xmlrpc.php?rsd', 'rpc' ) ) . '" />' . "\n";
 }
 
 /**
Index: src/wp-admin/plugin-editor.php
===================================================================
--- src/wp-admin/plugin-editor.php	(revision 35088)
+++ src/wp-admin/plugin-editor.php	(working copy)
@@ -171,8 +171,14 @@
 <?php elseif (isset($_GET['phperror'])) : ?>
  <div id="message" class="updated"><p><?php _e('This plugin has been deactivated because your changes resulted in a <strong>fatal error</strong>.') ?></p>
 	<?php
-		if ( wp_verify_nonce($_GET['_error_nonce'], 'plugin-activation-error_' . $file) ) { ?>
-	<iframe style="border:0" width="100%" height="70px" src="<?php bloginfo('wpurl'); ?>/wp-admin/plugins.php?action=error_scrape&amp;plugin=<?php echo esc_attr($file); ?>&amp;_wpnonce=<?php echo esc_attr($_GET['_error_nonce']); ?>"></iframe>
+		if ( wp_verify_nonce($_GET['_error_nonce'], 'plugin-activation-error_' . $file) ) {
+			$iframe_url = add_query_arg( array(
+				'action'   => 'error_scrape',
+				'plugin'   => urlencode( $file ),
+				'_wpnonce' => urlencode( $_GET['_error_nonce'] ),
+			), admin_url( 'plugins.php' ) );
+			?>
+	<iframe style="border:0" width="100%" height="70px" src="<?php echo esc_url( $iframe_url ); ?>"></iframe>
 	<?php } ?>
 </div>
 <?php endif; ?>
Index: src/wp-admin/plugins.php
===================================================================
--- src/wp-admin/plugins.php	(revision 35088)
+++ src/wp-admin/plugins.php	(working copy)
@@ -462,8 +462,14 @@
 	?>
 	<div id="message" class="error"><p><?php echo $errmsg; ?></p>
 	<?php
-		if ( !isset( $_GET['main'] ) && !isset($_GET['charsout']) && wp_verify_nonce($_GET['_error_nonce'], 'plugin-activation-error_' . $plugin) ) { ?>
-	<iframe style="border:0" width="100%" height="70px" src="<?php echo 'plugins.php?action=error_scrape&amp;plugin=' . esc_attr($plugin) . '&amp;_wpnonce=' . esc_attr($_GET['_error_nonce']); ?>"></iframe>
+		if ( !isset( $_GET['main'] ) && !isset($_GET['charsout']) && wp_verify_nonce($_GET['_error_nonce'], 'plugin-activation-error_' . $plugin) ) {
+			$iframe_url = add_query_arg( array(
+				'action'   => 'error_scrape',
+				'plugin'   => urlencode( $file ),
+				'_wpnonce' => urlencode( $_GET['_error_nonce'] ),
+			), admin_url( 'plugins.php' ) );
+		?>
+		<iframe style="border:0" width="100%" height="70px" src="<?php echo esc_url( $iframe_url ); ?>"></iframe>
 	<?php
 		}
 	?>