diff --git a/client/rest-high-level/src/main/java/org/elasticsearch/client/security/GetUsersResponse.java b/client/rest-high-level/src/main/java/org/elasticsearch/client/security/GetUsersResponse.java
index 107b93afe7ce4..39d4a25a64207 100644
--- a/client/rest-high-level/src/main/java/org/elasticsearch/client/security/GetUsersResponse.java
+++ b/client/rest-high-level/src/main/java/org/elasticsearch/client/security/GetUsersResponse.java
@@ -95,7 +95,7 @@ public int hashCode() {
     public static final ParseField ENABLED = new ParseField("enabled");
 
     @SuppressWarnings("unchecked")
-    public static final ConstructingObjectParser<ParsedUser, String> USER_PARSER = new ConstructingObjectParser<>("user_info",
+    public static final ConstructingObjectParser<ParsedUser, String> USER_PARSER = new ConstructingObjectParser<>("user_info", true,
         (constructorObjects) -> {
             int i = 0;
             final String username = (String) constructorObjects[i++];
diff --git a/client/rest-high-level/src/test/java/org/elasticsearch/client/security/GetUsersResponseTests.java b/client/rest-high-level/src/test/java/org/elasticsearch/client/security/GetUsersResponseTests.java
index 3025241bb3909..69db584287ceb 100644
--- a/client/rest-high-level/src/test/java/org/elasticsearch/client/security/GetUsersResponseTests.java
+++ b/client/rest-high-level/src/test/java/org/elasticsearch/client/security/GetUsersResponseTests.java
@@ -19,58 +19,97 @@
 package org.elasticsearch.client.security;
 
 import org.elasticsearch.client.security.user.User;
-import org.elasticsearch.common.xcontent.DeprecationHandler;
-import org.elasticsearch.common.xcontent.NamedXContentRegistry;
+import org.elasticsearch.common.bytes.BytesReference;
+import org.elasticsearch.common.xcontent.XContentBuilder;
 import org.elasticsearch.common.xcontent.XContentType;
+import org.elasticsearch.common.xcontent.json.JsonXContent;
 import org.elasticsearch.test.ESTestCase;
 import org.elasticsearch.test.EqualsHashCodeTestUtils;
+import org.elasticsearch.test.XContentTestUtils;
 
 import java.io.IOException;
+import java.util.ArrayList;
 import java.util.Arrays;
-import java.util.Collections;
 import java.util.HashMap;
 import java.util.HashSet;
+import java.util.List;
 import java.util.Map;
 import java.util.Set;
+import java.util.function.Predicate;
 import java.util.stream.Collectors;
 
-import static org.hamcrest.Matchers.equalTo;
+import static org.elasticsearch.test.AbstractXContentTestCase.xContentTester;
 
 /** tests the Response for getting users from the security HLRC */
 public class GetUsersResponseTests extends ESTestCase {
+
     public void testFromXContent() throws IOException {
-        String json =
-            "{\n" +
-                "  \"jacknich\": {\n" +
-                "    \"username\": \"jacknich\",\n" +
-                "    \"roles\": [\n" +
-                "      \"admin\", \"other_role1\"\n" +
-                "    ],\n" +
-                "    \"full_name\": \"Jack Nicholson\",\n" +
-                "    \"email\": \"jacknich@example.com\",\n" +
-                "    \"metadata\": { \"intelligence\" : 7 },\n" +
-                "    \"enabled\": true\n" +
-                "  }\n" +
-                "}";
-        final GetUsersResponse response = GetUsersResponse.fromXContent((XContentType.JSON.xContent().createParser(
-            new NamedXContentRegistry(Collections.emptyList()), new DeprecationHandler() {
-                @Override
-                public void usedDeprecatedName(String usedName, String modernName) {
-                }
+        xContentTester(this::createParser,
+            GetUsersResponseTests::createTestInstance,
+            this::toXContent,
+            GetUsersResponse::fromXContent)
+            .supportsUnknownFields(false)
+            .assertToXContentEquivalence(false)
+            .test();
+    }
+
+    private XContentBuilder toXContentUser(User user, boolean enabled, XContentBuilder builder) throws IOException {
+        XContentBuilder tempBuilder = JsonXContent.contentBuilder();
+        tempBuilder.startObject();
+        tempBuilder.field("username", user.getUsername());
+        tempBuilder.array("roles", user.getRoles().toArray());
+        tempBuilder.field("full_name", user.getFullName());
+        tempBuilder.field("email", user.getEmail());
+        tempBuilder.field("metadata", user.getMetadata());
+        tempBuilder.field("enabled", enabled);
+        tempBuilder.endObject();
+
+        // This sub object should support unknown fields, but metadata cannot contain complex extra objects or it will fail
+        Predicate<String> excludeFilter = path -> path.equals("metadata");
+        BytesReference newBytes = XContentTestUtils.insertRandomFields(XContentType.JSON, BytesReference.bytes(tempBuilder),
+            excludeFilter, random());
+        builder.rawValue(newBytes.streamInput(), XContentType.JSON);
+        return builder;
+    }
+
+    private XContentBuilder toXContent(GetUsersResponse response, XContentBuilder builder) throws IOException {
+        builder.startObject();
+
+        List<User> disabledUsers = new ArrayList<>(response.getUsers());
+        disabledUsers.removeAll(response.getEnabledUsers());
+
+        for (User user : disabledUsers) {
+            builder.field(user.getUsername());
+            toXContentUser(user, false, builder);
+        }
+        for (User user : response.getEnabledUsers()) {
+            builder.field(user.getUsername());
+            toXContentUser(user, true, builder);
+        }
+        builder.endObject();
+        return builder;
+    }
+
+    private static GetUsersResponse createTestInstance() {
+        final Set<User> users = new HashSet<>();
+        final Set<User> enabledUsers = new HashSet<>();
+        Map<String, Object> metadata = new HashMap<>();
+        metadata.put(randomAlphaOfLengthBetween(1, 5), randomInt());
 
-                @Override
-                public void usedDeprecatedField(String usedName, String replacedWith) {
-                }
-            }, json)));
-        assertThat(response.getUsers().size(), equalTo(1));
-        final User user = response.getUsers().iterator().next();
-        assertThat(user.getUsername(), equalTo("jacknich"));
-        assertThat(user.getRoles().size(), equalTo(2));
-        assertThat(user.getFullName(), equalTo("Jack Nicholson"));
-        assertThat(user.getEmail(), equalTo("jacknich@example.com"));
-        final Map<String, Object> metadata = new HashMap<>();
-        metadata.put("intelligence", 7);
-        assertThat(metadata, equalTo(user.getMetadata()));
+        final User user1 = new User(randomAlphaOfLength(8),
+            Arrays.asList(new String[] {randomAlphaOfLength(5), randomAlphaOfLength(5)}),
+            metadata, randomAlphaOfLength(10), null);
+        users.add(user1);
+        enabledUsers.add(user1);
+        Map<String, Object> metadata2 = new HashMap<>();
+        metadata2.put(randomAlphaOfLengthBetween(1, 5), randomInt());
+        metadata2.put(randomAlphaOfLengthBetween(1, 5), randomBoolean());
+
+        final User user2 = new User(randomAlphaOfLength(8),
+            Arrays.asList(new String[] {randomAlphaOfLength(5), randomAlphaOfLength(5)}),
+            metadata2, randomAlphaOfLength(10), null);
+        users.add(user2);
+        return new GetUsersResponse(users, enabledUsers);
     }
 
     public void testEqualsHashCode() {