Index: src/wp-admin/network/site-info.php
===================================================================
--- src/wp-admin/network/site-info.php	(revision 33141)
+++ src/wp-admin/network/site-info.php	(working copy)
@@ -42,6 +42,10 @@
 }
 
 $details = get_blog_details( $id );
+if ( ! $details ) {
+	wp_die( __( 'The requested site does not exist.' ) );
+}
+
 if ( ! can_edit_network( $details->site_id ) ) {
 	wp_die( __( 'You do not have permission to access this page.' ), 403 );
 }
Index: src/wp-admin/network/site-settings.php
===================================================================
--- src/wp-admin/network/site-settings.php	(revision 33141)
+++ src/wp-admin/network/site-settings.php	(working copy)
@@ -39,6 +39,10 @@
 	wp_die( __('Invalid site ID.') );
 
 $details = get_blog_details( $id );
+if ( ! $details ) {
+	wp_die( __( 'The requested site does not exist.' ) );
+}
+
 if ( !can_edit_network( $details->site_id ) )
 	wp_die( __( 'You do not have permission to access this page.' ), 403 );
 
Index: src/wp-admin/network/site-themes.php
===================================================================
--- src/wp-admin/network/site-themes.php	(revision 33141)
+++ src/wp-admin/network/site-themes.php	(working copy)
@@ -56,6 +56,10 @@
 $wp_list_table->prepare_items();
 
 $details = get_blog_details( $id );
+if ( ! $details ) {
+	wp_die( __( 'The requested site does not exist.' ) );
+}
+
 if ( !can_edit_network( $details->site_id ) )
 	wp_die( __( 'You do not have permission to access this page.' ), 403 );
 
Index: src/wp-admin/network/site-users.php
===================================================================
--- src/wp-admin/network/site-users.php	(revision 33141)
+++ src/wp-admin/network/site-users.php	(working copy)
@@ -49,6 +49,10 @@
 	wp_die( __('Invalid site ID.') );
 
 $details = get_blog_details( $id );
+if ( ! $details ) {
+	wp_die( __( 'The requested site does not exist' ) );
+}
+
 if ( ! can_edit_network( $details->site_id ) )
 	wp_die( __( 'You do not have permission to access this page.' ), 403 );