commit 2d69fde135302e8cff984bb2131ec69f2e396964
Author: Mark Thomas <markt@apache.org>
Date:   Tue Feb 6 11:41:16 2018 +0000

    git-svn-id: https://svn.apache.org/repos/asf/tomcat/tc7.0.x/trunk@1823309 13f79535-47bb-0310-9956-ffa450edef68

diff --git a/java/org/apache/catalina/realm/RealmBase.java b/java/org/apache/catalina/realm/RealmBase.java
index 2098c2e8cc..9697440d35 100644
--- java/org/apache/catalina/realm/RealmBase.java
+++ java/org/apache/catalina/realm/RealmBase.java
@@ -688,9 +688,9 @@ public abstract class RealmBase extends LifecycleMBeanBase implements Realm {

         // Check each defined security constraint
         String uri = request.getRequestPathMB().toString();
-        // Bug47080 - in rare cases this may be null
+        // Bug47080 - in rare cases this may be null or ""
         // Mapper treats as '/' do the same to prevent NPE
-        if (uri == null) {
+        if (uri == null || uri.length() == 0) {
             uri = "/";
         }

@@ -722,7 +722,8 @@ public abstract class RealmBase extends LifecycleMBeanBase implements Realm {
                 }

                 for(int k=0; k < patterns.length; k++) {
-                    if(uri.equals(patterns[k])) {
+                    // Exact match including special case for the context root.
+                    if(uri.equals(patterns[k]) || patterns[k].length() == 0 && uri.equals("/")) {
                         found = true;
                         if(collection[j].findMethod(method)) {
                             if(results == null) {
diff -up webapps/docs/changelog.xml.orig webapps/docs/changelog.xml
--- webapps/docs/changelog.xml.orig	2019-02-28 15:11:59.735767416 -0500
+++ webapps/docs/changelog.xml	2019-02-28 15:12:23.805697236 -0500
@@ -64,6 +64,10 @@
         When generating a redirect to a directory in the Default Servlet, avoid
         generating a protocol relative redirect. (markt)
       </fix>
+      <fix>
+        <bug>62067</bug>: Correctly apply security constraints mapped to the
+        context root using a URL pattern of <code>&quot;&quot;</code>. (markt)
+      </fix>
     </changelog>
   </subsection>
 </section>