diff --git a/src/core/server/elasticsearch/client/client_config.test.ts b/src/core/server/elasticsearch/client/client_config.test.ts
index ba6fba0051c05..e8083836d3c1e 100644
--- a/src/core/server/elasticsearch/client/client_config.test.ts
+++ b/src/core/server/elasticsearch/client/client_config.test.ts
@@ -19,7 +19,7 @@
 
 import { duration } from 'moment';
 import { ElasticsearchClientConfig, parseClientOptions } from './client_config';
-import { KIBANA_HEADERS } from '../kibana_headers';
+import { DEFAULT_HEADERS } from '../default_headers';
 
 const createConfig = (
   parts: Partial<ElasticsearchClientConfig> = {}
@@ -43,7 +43,7 @@ describe('parseClientOptions', () => {
     expect(parseClientOptions(config, false)).toEqual(
       expect.objectContaining({
         headers: {
-          ...KIBANA_HEADERS,
+          ...DEFAULT_HEADERS,
         },
       })
     );
@@ -61,7 +61,7 @@ describe('parseClientOptions', () => {
       expect(parseClientOptions(config, false)).toEqual(
         expect.objectContaining({
           headers: {
-            ...KIBANA_HEADERS,
+            ...DEFAULT_HEADERS,
             foo: 'bar',
             hello: 'dolly',
           },
@@ -71,7 +71,7 @@ describe('parseClientOptions', () => {
 
     it('`customHeaders` take precedence to default kibana headers', () => {
       const customHeader = {
-        [Object.keys(KIBANA_HEADERS)[0]]: 'foo',
+        [Object.keys(DEFAULT_HEADERS)[0]]: 'foo',
       };
       const config = createConfig({
         customHeaders: {
diff --git a/src/core/server/elasticsearch/client/client_config.ts b/src/core/server/elasticsearch/client/client_config.ts
index bdc9ee011829e..f24c0d86550b8 100644
--- a/src/core/server/elasticsearch/client/client_config.ts
+++ b/src/core/server/elasticsearch/client/client_config.ts
@@ -22,7 +22,7 @@ import { URL } from 'url';
 import { Duration } from 'moment';
 import { ClientOptions, NodeOptions } from '@elastic/elasticsearch';
 import { ElasticsearchConfig } from '../elasticsearch_config';
-import { KIBANA_HEADERS } from '../kibana_headers';
+import { DEFAULT_HEADERS } from '../default_headers';
 
 /**
  * Configuration options to be used to create a {@link IClusterClient | cluster client} using the
@@ -63,7 +63,7 @@ export function parseClientOptions(
     sniffOnStart: config.sniffOnStart,
     sniffOnConnectionFault: config.sniffOnConnectionFault,
     headers: {
-      ...KIBANA_HEADERS,
+      ...DEFAULT_HEADERS,
       ...config.customHeaders,
     },
   };
diff --git a/src/core/server/elasticsearch/client/cluster_client.test.ts b/src/core/server/elasticsearch/client/cluster_client.test.ts
index 6a3d828deb580..429fea65704d8 100644
--- a/src/core/server/elasticsearch/client/cluster_client.test.ts
+++ b/src/core/server/elasticsearch/client/cluster_client.test.ts
@@ -24,7 +24,7 @@ import { GetAuthHeaders } from '../../http';
 import { elasticsearchClientMock } from './mocks';
 import { ClusterClient } from './cluster_client';
 import { ElasticsearchClientConfig } from './client_config';
-import { KIBANA_HEADERS } from '../kibana_headers';
+import { DEFAULT_HEADERS } from '../default_headers';
 
 const createConfig = (
   parts: Partial<ElasticsearchClientConfig> = {}
@@ -128,7 +128,7 @@ describe('ClusterClient', () => {
 
       expect(scopedClient.child).toHaveBeenCalledTimes(1);
       expect(scopedClient.child).toHaveBeenCalledWith({
-        headers: { ...KIBANA_HEADERS, foo: 'bar', 'x-opaque-id': expect.any(String) },
+        headers: { ...DEFAULT_HEADERS, foo: 'bar', 'x-opaque-id': expect.any(String) },
       });
     });
 
@@ -148,7 +148,7 @@ describe('ClusterClient', () => {
 
       expect(scopedClient.child).toHaveBeenCalledTimes(1);
       expect(scopedClient.child).toHaveBeenCalledWith({
-        headers: { ...KIBANA_HEADERS, authorization: 'auth', 'x-opaque-id': expect.any(String) },
+        headers: { ...DEFAULT_HEADERS, authorization: 'auth', 'x-opaque-id': expect.any(String) },
       });
     });
 
@@ -172,7 +172,7 @@ describe('ClusterClient', () => {
 
       expect(scopedClient.child).toHaveBeenCalledTimes(1);
       expect(scopedClient.child).toHaveBeenCalledWith({
-        headers: { ...KIBANA_HEADERS, authorization: 'auth', 'x-opaque-id': expect.any(String) },
+        headers: { ...DEFAULT_HEADERS, authorization: 'auth', 'x-opaque-id': expect.any(String) },
       });
     });
 
@@ -194,7 +194,7 @@ describe('ClusterClient', () => {
       expect(scopedClient.child).toHaveBeenCalledTimes(1);
       expect(scopedClient.child).toHaveBeenCalledWith({
         headers: {
-          ...KIBANA_HEADERS,
+          ...DEFAULT_HEADERS,
           foo: 'bar',
           hello: 'dolly',
           'x-opaque-id': expect.any(String),
@@ -216,7 +216,7 @@ describe('ClusterClient', () => {
       expect(scopedClient.child).toHaveBeenCalledTimes(1);
       expect(scopedClient.child).toHaveBeenCalledWith({
         headers: {
-          ...KIBANA_HEADERS,
+          ...DEFAULT_HEADERS,
           'x-opaque-id': 'my-fake-id',
         },
       });
@@ -242,7 +242,7 @@ describe('ClusterClient', () => {
       expect(scopedClient.child).toHaveBeenCalledTimes(1);
       expect(scopedClient.child).toHaveBeenCalledWith({
         headers: {
-          ...KIBANA_HEADERS,
+          ...DEFAULT_HEADERS,
           foo: 'auth',
           hello: 'dolly',
           'x-opaque-id': expect.any(String),
@@ -270,7 +270,7 @@ describe('ClusterClient', () => {
       expect(scopedClient.child).toHaveBeenCalledTimes(1);
       expect(scopedClient.child).toHaveBeenCalledWith({
         headers: {
-          ...KIBANA_HEADERS,
+          ...DEFAULT_HEADERS,
           foo: 'request',
           hello: 'dolly',
           'x-opaque-id': expect.any(String),
@@ -279,7 +279,7 @@ describe('ClusterClient', () => {
     });
 
     it('respect the precedence of config headers over default headers', () => {
-      const headerKey = Object.keys(KIBANA_HEADERS)[0];
+      const headerKey = Object.keys(DEFAULT_HEADERS)[0];
       const config = createConfig({
         customHeaders: {
           [headerKey]: 'foo',
@@ -302,7 +302,7 @@ describe('ClusterClient', () => {
     });
 
     it('respect the precedence of request headers over default headers', () => {
-      const headerKey = Object.keys(KIBANA_HEADERS)[0];
+      const headerKey = Object.keys(DEFAULT_HEADERS)[0];
       const config = createConfig({
         requestHeadersWhitelist: [headerKey],
       });
@@ -343,7 +343,7 @@ describe('ClusterClient', () => {
       expect(scopedClient.child).toHaveBeenCalledTimes(1);
       expect(scopedClient.child).toHaveBeenCalledWith({
         headers: {
-          ...KIBANA_HEADERS,
+          ...DEFAULT_HEADERS,
           'x-opaque-id': 'from request',
         },
       });
@@ -367,7 +367,7 @@ describe('ClusterClient', () => {
 
       expect(scopedClient.child).toHaveBeenCalledTimes(1);
       expect(scopedClient.child).toHaveBeenCalledWith({
-        headers: { ...KIBANA_HEADERS, authorization: 'auth' },
+        headers: { ...DEFAULT_HEADERS, authorization: 'auth' },
       });
     });
 
@@ -391,7 +391,7 @@ describe('ClusterClient', () => {
 
       expect(scopedClient.child).toHaveBeenCalledTimes(1);
       expect(scopedClient.child).toHaveBeenCalledWith({
-        headers: { ...KIBANA_HEADERS, foo: 'bar' },
+        headers: { ...DEFAULT_HEADERS, foo: 'bar' },
       });
     });
   });
diff --git a/src/core/server/elasticsearch/client/cluster_client.ts b/src/core/server/elasticsearch/client/cluster_client.ts
index 3dcf82b02b29c..2294df89d4274 100644
--- a/src/core/server/elasticsearch/client/cluster_client.ts
+++ b/src/core/server/elasticsearch/client/cluster_client.ts
@@ -26,7 +26,7 @@ import { ElasticsearchClient } from './types';
 import { configureClient } from './configure_client';
 import { ElasticsearchClientConfig } from './client_config';
 import { ScopedClusterClient, IScopedClusterClient } from './scoped_cluster_client';
-import { KIBANA_HEADERS } from '../kibana_headers';
+import { DEFAULT_HEADERS } from '../default_headers';
 
 const noop = () => undefined;
 
@@ -109,7 +109,7 @@ export class ClusterClient implements ICustomClusterClient {
     }
 
     return {
-      ...KIBANA_HEADERS,
+      ...DEFAULT_HEADERS,
       ...this.config.customHeaders,
       ...scopedHeaders,
     };
diff --git a/src/core/server/elasticsearch/kibana_headers.ts b/src/core/server/elasticsearch/default_headers.ts
similarity index 90%
rename from src/core/server/elasticsearch/kibana_headers.ts
rename to src/core/server/elasticsearch/default_headers.ts
index 6caac8a23bd84..61be0cacbb805 100644
--- a/src/core/server/elasticsearch/kibana_headers.ts
+++ b/src/core/server/elasticsearch/default_headers.ts
@@ -17,6 +17,8 @@
  * under the License.
  */
 
-export const KIBANA_HEADERS = {
+import { deepFreeze } from '@kbn/std';
+
+export const DEFAULT_HEADERS = deepFreeze({
   'x-elastic-product-origin': 'kibana',
-};
+});
diff --git a/src/core/server/elasticsearch/legacy/elasticsearch_client_config.test.ts b/src/core/server/elasticsearch/legacy/elasticsearch_client_config.test.ts
index 3176f3b8a56e9..1e85932caa8ae 100644
--- a/src/core/server/elasticsearch/legacy/elasticsearch_client_config.test.ts
+++ b/src/core/server/elasticsearch/legacy/elasticsearch_client_config.test.ts
@@ -23,7 +23,7 @@ import {
   LegacyElasticsearchClientConfig,
   parseElasticsearchClientConfig,
 } from './elasticsearch_client_config';
-import { KIBANA_HEADERS } from '../kibana_headers';
+import { DEFAULT_HEADERS } from '../default_headers';
 const logger = loggingSystemMock.create();
 afterEach(() => jest.clearAllMocks());
 
@@ -348,7 +348,7 @@ describe('#auth', () => {
 
 describe('#customHeaders', () => {
   test('override the default headers', () => {
-    const headerKey = Object.keys(KIBANA_HEADERS)[0];
+    const headerKey = Object.keys(DEFAULT_HEADERS)[0];
     const parsedConfig = parseElasticsearchClientConfig(
       {
         apiVersion: 'master',
diff --git a/src/core/server/elasticsearch/legacy/elasticsearch_client_config.ts b/src/core/server/elasticsearch/legacy/elasticsearch_client_config.ts
index 6404070e0556b..35681ac7a247d 100644
--- a/src/core/server/elasticsearch/legacy/elasticsearch_client_config.ts
+++ b/src/core/server/elasticsearch/legacy/elasticsearch_client_config.ts
@@ -25,7 +25,7 @@ import url from 'url';
 import { pick } from '@kbn/std';
 import { Logger } from '../../logging';
 import { ElasticsearchConfig } from '../elasticsearch_config';
-import { KIBANA_HEADERS } from '../kibana_headers';
+import { DEFAULT_HEADERS } from '../default_headers';
 
 /**
  * @privateRemarks Config that consumers can pass to the Elasticsearch JS client is complex and includes
@@ -132,7 +132,7 @@ export function parseElasticsearchClientConfig(
         path: uri.pathname,
         query: uri.query,
         headers: {
-          ...KIBANA_HEADERS,
+          ...DEFAULT_HEADERS,
           ...config.customHeaders,
         },
       };