diff -ur accumulo-1.9.1/server/monitor/src/main/java/org/apache/accumulo/monitor/EmbeddedWebServer.java accumulo-1.9.1-mod/server/monitor/src/main/java/org/apache/accumulo/monitor/EmbeddedWebServer.java
--- accumulo-1.9.1/server/monitor/src/main/java/org/apache/accumulo/monitor/EmbeddedWebServer.java	2018-05-09 21:27:43.000000000 -0400
+++ accumulo-1.9.1-mod/server/monitor/src/main/java/org/apache/accumulo/monitor/EmbeddedWebServer.java	2018-07-06 15:18:03.410228168 -0400
@@ -85,7 +85,7 @@
 
     handler = new ServletContextHandler(server, "/", new SessionHandler(),
         new ConstraintSecurityHandler(), null, null);
-    handler.getSessionHandler().getSessionManager().getSessionCookieConfig().setHttpOnly(true);
+    handler.getSessionHandler().setHttpOnly(true);
 
     disableTrace("/");
   }