diff --git a/src/core/server/http/http_server.mocks.ts b/src/core/server/http/http_server.mocks.ts
index 33a98127aa630..fcc232345a802 100644
--- a/src/core/server/http/http_server.mocks.ts
+++ b/src/core/server/http/http_server.mocks.ts
@@ -18,6 +18,7 @@
  */
 import { Request } from 'hapi';
 import { merge } from 'lodash';
+import { Socket } from 'net';
 
 import querystring from 'querystring';
 
@@ -37,6 +38,7 @@ interface RequestFixtureOptions {
   query?: Record<string, any>;
   path?: string;
   method?: RouteMethod;
+  socket?: Socket;
 }
 
 function createKibanaRequestMock({
@@ -46,6 +48,7 @@ function createKibanaRequestMock({
   body = {},
   query = {},
   method = 'get',
+  socket = new Socket(),
 }: RequestFixtureOptions = {}) {
   const queryString = querystring.stringify(query);
   return KibanaRequest.from(
@@ -63,7 +66,7 @@ function createKibanaRequestMock({
       },
       route: { settings: {} },
       raw: {
-        req: {},
+        req: { socket },
       },
     } as any,
     {
diff --git a/x-pack/legacy/server/lib/esjs_shield_plugin.js b/x-pack/legacy/server/lib/esjs_shield_plugin.js
index 83f050ee5ce59..e0a69b5ce538e 100644
--- a/x-pack/legacy/server/lib/esjs_shield_plugin.js
+++ b/x-pack/legacy/server/lib/esjs_shield_plugin.js
@@ -536,5 +536,21 @@
         fmt: '/_security/api_key',
       },
     });
+
+    /**
+     * Gets an access token in exchange to the certificate chain for the target subject distinguished name.
+     *
+     * @param {string[]} x509_certificate_chain An ordered array of base64-encoded (Section 4 of RFC4648 - not
+     * base64url-encoded) DER PKIX certificate values.
+     *
+     * @returns {{access_token: string, type: string, expires_in: number}}
+     */
+    shield.delegatePKI = ca({
+      method: 'POST',
+      needBody: true,
+      url: {
+        fmt: '/_security/delegate_pki',
+      },
+    });
   };
 }));
diff --git a/x-pack/plugins/security/server/authentication/authenticator.ts b/x-pack/plugins/security/server/authentication/authenticator.ts
index f01047eff7aa3..b3f34b023d8ee 100644
--- a/x-pack/plugins/security/server/authentication/authenticator.ts
+++ b/x-pack/plugins/security/server/authentication/authenticator.ts
@@ -25,6 +25,7 @@ import {
   SAMLAuthenticationProvider,
   TokenAuthenticationProvider,
   OIDCAuthenticationProvider,
+  PKIAuthenticationProvider,
   isSAMLRequestQuery,
 } from './providers';
 import { AuthenticationResult } from './authentication_result';
@@ -98,6 +99,7 @@ const providerMap = new Map<
   ['saml', SAMLAuthenticationProvider],
   ['token', TokenAuthenticationProvider],
   ['oidc', OIDCAuthenticationProvider],
+  ['pki', PKIAuthenticationProvider],
 ]);
 
 function assertRequest(request: KibanaRequest) {
diff --git a/x-pack/plugins/security/server/authentication/providers/base.mock.ts b/x-pack/plugins/security/server/authentication/providers/base.mock.ts
index 8e7410ddec077..a659786f4aeff 100644
--- a/x-pack/plugins/security/server/authentication/providers/base.mock.ts
+++ b/x-pack/plugins/security/server/authentication/providers/base.mock.ts
@@ -7,12 +7,20 @@
 import sinon from 'sinon';
 import { ScopedClusterClient } from '../../../../../../src/core/server';
 import { Tokens } from '../tokens';
-import { loggingServiceMock, httpServiceMock } from '../../../../../../src/core/server/mocks';
+import {
+  loggingServiceMock,
+  httpServiceMock,
+  elasticsearchServiceMock,
+} from '../../../../../../src/core/server/mocks';
 
 export type MockAuthenticationProviderOptions = ReturnType<
   typeof mockAuthenticationProviderOptions
 >;
 
+export type MockAuthenticationProviderOptionsWithJest = ReturnType<
+  typeof mockAuthenticationProviderOptionsWithJest
+>;
+
 export function mockScopedClusterClient(
   client: MockAuthenticationProviderOptions['client'],
   requestMatcher: sinon.SinonMatcher = sinon.match.any
@@ -34,3 +42,16 @@ export function mockAuthenticationProviderOptions() {
     tokens: sinon.createStubInstance(Tokens),
   };
 }
+
+// Will be renamed to mockAuthenticationProviderOptions as soon as we migrate all providers tests to Jest.
+export function mockAuthenticationProviderOptionsWithJest() {
+  const basePath = httpServiceMock.createSetupContract().basePath;
+  basePath.get.mockReturnValue('/base-path');
+
+  return {
+    client: elasticsearchServiceMock.createClusterClient(),
+    logger: loggingServiceMock.create().get(),
+    basePath,
+    tokens: { refresh: jest.fn(), invalidate: jest.fn() },
+  };
+}
diff --git a/x-pack/plugins/security/server/authentication/providers/index.ts b/x-pack/plugins/security/server/authentication/providers/index.ts
index fef3be16c8d91..af0b90766e859 100644
--- a/x-pack/plugins/security/server/authentication/providers/index.ts
+++ b/x-pack/plugins/security/server/authentication/providers/index.ts
@@ -14,3 +14,4 @@ export { KerberosAuthenticationProvider } from './kerberos';
 export { SAMLAuthenticationProvider, isSAMLRequestQuery } from './saml';
 export { TokenAuthenticationProvider } from './token';
 export { OIDCAuthenticationProvider, OIDCAuthenticationFlow } from './oidc';
+export { PKIAuthenticationProvider } from './pki';
diff --git a/x-pack/plugins/security/server/authentication/providers/pki.test.ts b/x-pack/plugins/security/server/authentication/providers/pki.test.ts
new file mode 100644
index 0000000000000..35d827c3a9bd1
--- /dev/null
+++ b/x-pack/plugins/security/server/authentication/providers/pki.test.ts
@@ -0,0 +1,589 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License;
+ * you may not use this file except in compliance with the Elastic License.
+ */
+
+jest.mock('net');
+jest.mock('tls');
+
+import { PeerCertificate, TLSSocket } from 'tls';
+import { errors } from 'elasticsearch';
+
+import { elasticsearchServiceMock, httpServerMock } from '../../../../../../src/core/server/mocks';
+import { mockAuthenticatedUser } from '../../../common/model/authenticated_user.mock';
+import {
+  MockAuthenticationProviderOptionsWithJest,
+  mockAuthenticationProviderOptionsWithJest,
+} from './base.mock';
+
+import { PKIAuthenticationProvider } from './pki';
+import {
+  ElasticsearchErrorHelpers,
+  ScopedClusterClient,
+} from '../../../../../../src/core/server/elasticsearch';
+import { Socket } from 'net';
+import { getErrorStatusCode } from '../../errors';
+
+interface MockPeerCertificate extends Partial<PeerCertificate> {
+  issuerCertificate: MockPeerCertificate;
+  fingerprint256: string;
+}
+
+function getMockPeerCertificate(chain: string[] | string) {
+  const mockPeerCertificate = {} as MockPeerCertificate;
+
+  (Array.isArray(chain) ? chain : [chain]).reduce(
+    (certificate, fingerprint, index, fingerprintChain) => {
+      certificate.fingerprint256 = fingerprint;
+      certificate.raw = { toString: (enc: string) => `fingerprint:${fingerprint}:${enc}` };
+
+      // Imitate self-signed certificate that is issuer for itself.
+      certificate.issuerCertificate = index === fingerprintChain.length - 1 ? certificate : {};
+
+      return certificate.issuerCertificate;
+    },
+    mockPeerCertificate as Record<string, any>
+  );
+
+  return mockPeerCertificate;
+}
+
+function getMockSocket({
+  authorized = false,
+  peerCertificate = null,
+}: {
+  authorized?: boolean;
+  peerCertificate?: MockPeerCertificate | null;
+} = {}) {
+  const socket = new TLSSocket(new Socket());
+  socket.authorized = authorized;
+  socket.getPeerCertificate = jest.fn().mockReturnValue(peerCertificate);
+  return socket;
+}
+
+describe('PKIAuthenticationProvider', () => {
+  let provider: PKIAuthenticationProvider;
+  let mockOptions: MockAuthenticationProviderOptionsWithJest;
+  beforeEach(() => {
+    mockOptions = mockAuthenticationProviderOptionsWithJest();
+    provider = new PKIAuthenticationProvider(mockOptions);
+  });
+
+  afterEach(() => jest.clearAllMocks());
+
+  describe('`authenticate` method', () => {
+    it('does not handle `authorization` header with unsupported schema even if state contains a valid token.', async () => {
+      const request = httpServerMock.createKibanaRequest({
+        headers: { authorization: 'Basic some:credentials' },
+      });
+      const state = {
+        accessToken: 'some-valid-token',
+        peerCertificateFingerprint256: '2A:7A:C2:DD',
+      };
+
+      const authenticationResult = await provider.authenticate(request, state);
+
+      expect(mockOptions.client.asScoped).not.toHaveBeenCalled();
+      expect(mockOptions.client.callAsInternalUser).not.toHaveBeenCalled();
+      expect(request.headers.authorization).toBe('Basic some:credentials');
+      expect(authenticationResult.notHandled()).toBe(true);
+    });
+
+    it('does not handle requests without certificate.', async () => {
+      const request = httpServerMock.createKibanaRequest({
+        socket: getMockSocket({ authorized: true }),
+      });
+
+      const authenticationResult = await provider.authenticate(request, null);
+
+      expect(authenticationResult.notHandled()).toBe(true);
+      expect(mockOptions.client.asScoped).not.toHaveBeenCalled();
+      expect(mockOptions.client.callAsInternalUser).not.toHaveBeenCalled();
+    });
+
+    it('does not handle unauthorized requests.', async () => {
+      const request = httpServerMock.createKibanaRequest({
+        socket: getMockSocket({ peerCertificate: getMockPeerCertificate('2A:7A:C2:DD') }),
+      });
+
+      const authenticationResult = await provider.authenticate(request, null);
+
+      expect(authenticationResult.notHandled()).toBe(true);
+      expect(mockOptions.client.asScoped).not.toHaveBeenCalled();
+      expect(mockOptions.client.callAsInternalUser).not.toHaveBeenCalled();
+    });
+
+    it('fails with non-401 error if state is available, peer is authorized, but certificate is not available.', async () => {
+      const request = httpServerMock.createKibanaRequest({
+        socket: getMockSocket({ authorized: true }),
+      });
+
+      const state = { accessToken: 'token', peerCertificateFingerprint256: '2A:7A:C2:DD' };
+
+      const authenticationResult = await provider.authenticate(request, state);
+      expect(authenticationResult.failed()).toBe(true);
+      expect(authenticationResult.error).toMatchInlineSnapshot(
+        `[Error: Peer certificate is not available]`
+      );
+      expect(authenticationResult.authResponseHeaders).toBeUndefined();
+      expect(mockOptions.tokens.invalidate).not.toHaveBeenCalled();
+    });
+
+    it('invalidates token and fails with 401 if state is present, but peer certificate is not.', async () => {
+      const request = httpServerMock.createKibanaRequest({ socket: getMockSocket() });
+      const state = { accessToken: 'token', peerCertificateFingerprint256: '2A:7A:C2:DD' };
+
+      const authenticationResult = await provider.authenticate(request, state);
+
+      expect(authenticationResult.failed()).toBe(true);
+      expect(getErrorStatusCode(authenticationResult.error)).toBe(401);
+
+      expect(mockOptions.tokens.invalidate).toHaveBeenCalledTimes(1);
+      expect(mockOptions.tokens.invalidate).toHaveBeenCalledWith({
+        accessToken: state.accessToken,
+      });
+    });
+
+    it('invalidates token and fails with 401 if new certificate is present, but not authorized.', async () => {
+      const request = httpServerMock.createKibanaRequest({
+        socket: getMockSocket({ peerCertificate: getMockPeerCertificate('2A:7A:C2:DD') }),
+      });
+      const state = { accessToken: 'token', peerCertificateFingerprint256: '2A:7A:C2:DD' };
+
+      const authenticationResult = await provider.authenticate(request, state);
+
+      expect(authenticationResult.failed()).toBe(true);
+      expect(getErrorStatusCode(authenticationResult.error)).toBe(401);
+
+      expect(mockOptions.tokens.invalidate).toHaveBeenCalledTimes(1);
+      expect(mockOptions.tokens.invalidate).toHaveBeenCalledWith({
+        accessToken: state.accessToken,
+      });
+    });
+
+    it('gets an access token in exchange to peer certificate chain and stores it in the state.', async () => {
+      const user = mockAuthenticatedUser();
+      const request = httpServerMock.createKibanaRequest({
+        headers: {},
+        socket: getMockSocket({
+          authorized: true,
+          peerCertificate: getMockPeerCertificate(['2A:7A:C2:DD', '3B:8B:D3:EE']),
+        }),
+      });
+
+      const mockScopedClusterClient = elasticsearchServiceMock.createScopedClusterClient();
+      mockScopedClusterClient.callAsCurrentUser.mockResolvedValue(user);
+      mockOptions.client.asScoped.mockReturnValue(
+        (mockScopedClusterClient as unknown) as jest.Mocked<ScopedClusterClient>
+      );
+      mockOptions.client.callAsInternalUser.mockResolvedValue({ access_token: 'access-token' });
+
+      const authenticationResult = await provider.authenticate(request);
+
+      expect(mockOptions.client.callAsInternalUser).toHaveBeenCalledTimes(1);
+      expect(mockOptions.client.callAsInternalUser).toHaveBeenCalledWith('shield.delegatePKI', {
+        body: {
+          x509_certificate_chain: [
+            'fingerprint:2A:7A:C2:DD:base64',
+            'fingerprint:3B:8B:D3:EE:base64',
+          ],
+        },
+      });
+
+      expect(mockOptions.client.asScoped).toHaveBeenCalledTimes(1);
+      expect(mockOptions.client.asScoped).toHaveBeenCalledWith({
+        headers: { authorization: `Bearer access-token` },
+      });
+      expect(mockScopedClusterClient.callAsCurrentUser).toHaveBeenCalledTimes(1);
+      expect(mockScopedClusterClient.callAsCurrentUser).toHaveBeenCalledWith('shield.authenticate');
+
+      expect(request.headers).not.toHaveProperty('authorization');
+      expect(authenticationResult.succeeded()).toBe(true);
+      expect(authenticationResult.user).toBe(user);
+      expect(authenticationResult.authHeaders).toEqual({ authorization: 'Bearer access-token' });
+      expect(authenticationResult.authResponseHeaders).toBeUndefined();
+      expect(authenticationResult.state).toEqual({
+        accessToken: 'access-token',
+        peerCertificateFingerprint256: '2A:7A:C2:DD',
+      });
+    });
+
+    it('gets an access token in exchange to a self-signed certificate and stores it in the state.', async () => {
+      const user = mockAuthenticatedUser();
+      const request = httpServerMock.createKibanaRequest({
+        headers: {},
+        socket: getMockSocket({
+          authorized: true,
+          peerCertificate: getMockPeerCertificate('2A:7A:C2:DD'),
+        }),
+      });
+
+      const mockScopedClusterClient = elasticsearchServiceMock.createScopedClusterClient();
+      mockScopedClusterClient.callAsCurrentUser.mockResolvedValue(user);
+      mockOptions.client.asScoped.mockReturnValue(
+        (mockScopedClusterClient as unknown) as jest.Mocked<ScopedClusterClient>
+      );
+      mockOptions.client.callAsInternalUser.mockResolvedValue({ access_token: 'access-token' });
+
+      const authenticationResult = await provider.authenticate(request);
+
+      expect(mockOptions.client.callAsInternalUser).toHaveBeenCalledTimes(1);
+      expect(mockOptions.client.callAsInternalUser).toHaveBeenCalledWith('shield.delegatePKI', {
+        body: { x509_certificate_chain: ['fingerprint:2A:7A:C2:DD:base64'] },
+      });
+
+      expect(mockOptions.client.asScoped).toHaveBeenCalledTimes(1);
+      expect(mockOptions.client.asScoped).toHaveBeenCalledWith({
+        headers: { authorization: `Bearer access-token` },
+      });
+      expect(mockScopedClusterClient.callAsCurrentUser).toHaveBeenCalledTimes(1);
+      expect(mockScopedClusterClient.callAsCurrentUser).toHaveBeenCalledWith('shield.authenticate');
+
+      expect(request.headers).not.toHaveProperty('authorization');
+      expect(authenticationResult.succeeded()).toBe(true);
+      expect(authenticationResult.user).toBe(user);
+      expect(authenticationResult.authHeaders).toEqual({ authorization: 'Bearer access-token' });
+      expect(authenticationResult.authResponseHeaders).toBeUndefined();
+      expect(authenticationResult.state).toEqual({
+        accessToken: 'access-token',
+        peerCertificateFingerprint256: '2A:7A:C2:DD',
+      });
+    });
+
+    it('invalidates existing token and gets a new one if fingerprints do not match.', async () => {
+      const user = mockAuthenticatedUser();
+      const request = httpServerMock.createKibanaRequest({
+        socket: getMockSocket({
+          authorized: true,
+          peerCertificate: getMockPeerCertificate(['2A:7A:C2:DD', '3B:8B:D3:EE']),
+        }),
+      });
+      const state = { accessToken: 'existing-token', peerCertificateFingerprint256: '3A:9A:C5:DD' };
+
+      const mockScopedClusterClient = elasticsearchServiceMock.createScopedClusterClient();
+      mockScopedClusterClient.callAsCurrentUser.mockResolvedValue(user);
+      mockOptions.client.asScoped.mockReturnValue(
+        (mockScopedClusterClient as unknown) as jest.Mocked<ScopedClusterClient>
+      );
+      mockOptions.client.callAsInternalUser.mockResolvedValue({ access_token: 'access-token' });
+
+      const authenticationResult = await provider.authenticate(request, state);
+
+      expect(mockOptions.tokens.invalidate).toHaveBeenCalledTimes(1);
+      expect(mockOptions.tokens.invalidate).toHaveBeenCalledWith({
+        accessToken: state.accessToken,
+      });
+
+      expect(mockOptions.client.callAsInternalUser).toHaveBeenCalledTimes(1);
+      expect(mockOptions.client.callAsInternalUser).toHaveBeenCalledWith('shield.delegatePKI', {
+        body: {
+          x509_certificate_chain: [
+            'fingerprint:2A:7A:C2:DD:base64',
+            'fingerprint:3B:8B:D3:EE:base64',
+          ],
+        },
+      });
+
+      expect(request.headers).not.toHaveProperty('authorization');
+      expect(authenticationResult.succeeded()).toBe(true);
+      expect(authenticationResult.user).toBe(user);
+      expect(authenticationResult.authHeaders).toEqual({ authorization: 'Bearer access-token' });
+      expect(authenticationResult.authResponseHeaders).toBeUndefined();
+      expect(authenticationResult.state).toEqual({
+        accessToken: 'access-token',
+        peerCertificateFingerprint256: '2A:7A:C2:DD',
+      });
+    });
+
+    it('gets a new access token even if existing token is expired.', async () => {
+      const user = mockAuthenticatedUser();
+      const request = httpServerMock.createKibanaRequest({
+        socket: getMockSocket({
+          authorized: true,
+          peerCertificate: getMockPeerCertificate(['2A:7A:C2:DD', '3B:8B:D3:EE']),
+        }),
+      });
+      const state = { accessToken: 'existing-token', peerCertificateFingerprint256: '2A:7A:C2:DD' };
+
+      const mockScopedClusterClient = elasticsearchServiceMock.createScopedClusterClient();
+      mockScopedClusterClient.callAsCurrentUser
+        // In response to call with an expired token.
+        .mockRejectedValueOnce(ElasticsearchErrorHelpers.decorateNotAuthorizedError(new Error()))
+        // In response to a call with a new token.
+        .mockResolvedValueOnce(user);
+      mockOptions.client.asScoped.mockReturnValue(
+        (mockScopedClusterClient as unknown) as jest.Mocked<ScopedClusterClient>
+      );
+      mockOptions.client.callAsInternalUser.mockResolvedValue({ access_token: 'access-token' });
+
+      const authenticationResult = await provider.authenticate(request, state);
+
+      expect(mockOptions.client.callAsInternalUser).toHaveBeenCalledTimes(1);
+      expect(mockOptions.client.callAsInternalUser).toHaveBeenCalledWith('shield.delegatePKI', {
+        body: {
+          x509_certificate_chain: [
+            'fingerprint:2A:7A:C2:DD:base64',
+            'fingerprint:3B:8B:D3:EE:base64',
+          ],
+        },
+      });
+
+      expect(request.headers).not.toHaveProperty('authorization');
+      expect(authenticationResult.succeeded()).toBe(true);
+      expect(authenticationResult.user).toBe(user);
+      expect(authenticationResult.authHeaders).toEqual({ authorization: 'Bearer access-token' });
+      expect(authenticationResult.authResponseHeaders).toBeUndefined();
+      expect(authenticationResult.state).toEqual({
+        accessToken: 'access-token',
+        peerCertificateFingerprint256: '2A:7A:C2:DD',
+      });
+    });
+
+    it('fails with 401 if existing token is expired, but certificate is not present.', async () => {
+      const request = httpServerMock.createKibanaRequest({ socket: getMockSocket() });
+      const state = { accessToken: 'existing-token', peerCertificateFingerprint256: '2A:7A:C2:DD' };
+
+      const mockScopedClusterClient = elasticsearchServiceMock.createScopedClusterClient();
+      mockScopedClusterClient.callAsCurrentUser.mockRejectedValue(
+        ElasticsearchErrorHelpers.decorateNotAuthorizedError(new Error())
+      );
+      mockOptions.client.asScoped.mockReturnValue(
+        (mockScopedClusterClient as unknown) as jest.Mocked<ScopedClusterClient>
+      );
+
+      const authenticationResult = await provider.authenticate(request, state);
+
+      expect(mockOptions.client.callAsInternalUser).not.toHaveBeenCalled();
+
+      expect(request.headers).not.toHaveProperty('authorization');
+      expect(authenticationResult.failed()).toBe(true);
+      expect(getErrorStatusCode(authenticationResult.error)).toBe(401);
+      expect(authenticationResult.authResponseHeaders).toBeUndefined();
+    });
+
+    it('fails if could not retrieve an access token in exchange to peer certificate chain.', async () => {
+      const request = httpServerMock.createKibanaRequest({
+        socket: getMockSocket({
+          authorized: true,
+          peerCertificate: getMockPeerCertificate('2A:7A:C2:DD'),
+        }),
+      });
+
+      const failureReason = ElasticsearchErrorHelpers.decorateNotAuthorizedError(new Error());
+      mockOptions.client.callAsInternalUser.mockRejectedValue(failureReason);
+
+      const authenticationResult = await provider.authenticate(request);
+
+      expect(mockOptions.client.callAsInternalUser).toHaveBeenCalledTimes(1);
+      expect(mockOptions.client.callAsInternalUser).toHaveBeenCalledWith('shield.delegatePKI', {
+        body: { x509_certificate_chain: ['fingerprint:2A:7A:C2:DD:base64'] },
+      });
+
+      expect(request.headers).not.toHaveProperty('authorization');
+      expect(authenticationResult.failed()).toBe(true);
+      expect(authenticationResult.error).toBe(failureReason);
+      expect(authenticationResult.authResponseHeaders).toBeUndefined();
+    });
+
+    it('fails if could not retrieve user using the new access token.', async () => {
+      const request = httpServerMock.createKibanaRequest({
+        headers: {},
+        socket: getMockSocket({
+          authorized: true,
+          peerCertificate: getMockPeerCertificate('2A:7A:C2:DD'),
+        }),
+      });
+
+      const failureReason = ElasticsearchErrorHelpers.decorateNotAuthorizedError(new Error());
+      const mockScopedClusterClient = elasticsearchServiceMock.createScopedClusterClient();
+      mockScopedClusterClient.callAsCurrentUser.mockRejectedValue(failureReason);
+      mockOptions.client.asScoped.mockReturnValue(
+        (mockScopedClusterClient as unknown) as jest.Mocked<ScopedClusterClient>
+      );
+      mockOptions.client.callAsInternalUser.mockResolvedValue({ access_token: 'access-token' });
+
+      const authenticationResult = await provider.authenticate(request);
+
+      expect(mockOptions.client.callAsInternalUser).toHaveBeenCalledTimes(1);
+      expect(mockOptions.client.callAsInternalUser).toHaveBeenCalledWith('shield.delegatePKI', {
+        body: { x509_certificate_chain: ['fingerprint:2A:7A:C2:DD:base64'] },
+      });
+
+      expect(mockOptions.client.asScoped).toHaveBeenCalledTimes(1);
+      expect(mockOptions.client.asScoped).toHaveBeenCalledWith({
+        headers: { authorization: `Bearer access-token` },
+      });
+      expect(mockScopedClusterClient.callAsCurrentUser).toHaveBeenCalledTimes(1);
+      expect(mockScopedClusterClient.callAsCurrentUser).toHaveBeenCalledWith('shield.authenticate');
+
+      expect(request.headers).not.toHaveProperty('authorization');
+      expect(authenticationResult.failed()).toBe(true);
+      expect(authenticationResult.error).toBe(failureReason);
+      expect(authenticationResult.authResponseHeaders).toBeUndefined();
+    });
+
+    it('succeeds if state contains a valid token.', async () => {
+      const user = mockAuthenticatedUser();
+      const state = { accessToken: 'token', peerCertificateFingerprint256: '2A:7A:C2:DD' };
+      const request = httpServerMock.createKibanaRequest({
+        socket: getMockSocket({
+          authorized: true,
+          peerCertificate: getMockPeerCertificate(state.peerCertificateFingerprint256),
+        }),
+      });
+
+      const mockScopedClusterClient = elasticsearchServiceMock.createScopedClusterClient();
+      mockScopedClusterClient.callAsCurrentUser.mockResolvedValue(user);
+      mockOptions.client.asScoped.mockReturnValue(
+        (mockScopedClusterClient as unknown) as jest.Mocked<ScopedClusterClient>
+      );
+
+      const authenticationResult = await provider.authenticate(request, state);
+
+      expect(mockOptions.client.callAsInternalUser).not.toHaveBeenCalled();
+
+      expect(request.headers).not.toHaveProperty('authorization');
+      expect(authenticationResult.succeeded()).toBe(true);
+      expect(authenticationResult.authHeaders).toEqual({
+        authorization: `Bearer ${state.accessToken}`,
+      });
+      expect(authenticationResult.user).toBe(user);
+      expect(authenticationResult.state).toBeUndefined();
+    });
+
+    it('fails if token from the state is rejected because of unknown reason.', async () => {
+      const state = { accessToken: 'token', peerCertificateFingerprint256: '2A:7A:C2:DD' };
+      const request = httpServerMock.createKibanaRequest({
+        socket: getMockSocket({
+          authorized: true,
+          peerCertificate: getMockPeerCertificate(state.peerCertificateFingerprint256),
+        }),
+      });
+
+      const mockScopedClusterClient = elasticsearchServiceMock.createScopedClusterClient();
+      mockScopedClusterClient.callAsCurrentUser.mockRejectedValue(new errors.ServiceUnavailable());
+      mockOptions.client.asScoped.mockReturnValue(
+        (mockScopedClusterClient as unknown) as jest.Mocked<ScopedClusterClient>
+      );
+
+      const authenticationResult = await provider.authenticate(request, state);
+
+      expect(authenticationResult.failed()).toBe(true);
+      expect(authenticationResult.error).toHaveProperty('status', 503);
+      expect(authenticationResult.authResponseHeaders).toBeUndefined();
+    });
+
+    it('succeeds if `authorization` contains a valid token.', async () => {
+      const user = mockAuthenticatedUser();
+      const request = httpServerMock.createKibanaRequest({
+        headers: { authorization: 'Bearer some-valid-token' },
+      });
+
+      const mockScopedClusterClient = elasticsearchServiceMock.createScopedClusterClient();
+      mockScopedClusterClient.callAsCurrentUser.mockResolvedValue(user);
+      mockOptions.client.asScoped.mockReturnValue(
+        (mockScopedClusterClient as unknown) as jest.Mocked<ScopedClusterClient>
+      );
+
+      const authenticationResult = await provider.authenticate(request);
+
+      expect(request.headers.authorization).toBe('Bearer some-valid-token');
+      expect(authenticationResult.succeeded()).toBe(true);
+      expect(authenticationResult.authHeaders).toBeUndefined();
+      expect(authenticationResult.user).toBe(user);
+      expect(authenticationResult.state).toBeUndefined();
+    });
+
+    it('fails if token from `authorization` header is rejected.', async () => {
+      const request = httpServerMock.createKibanaRequest({
+        headers: { authorization: 'Bearer some-invalid-token' },
+      });
+
+      const failureReason = ElasticsearchErrorHelpers.decorateNotAuthorizedError(new Error());
+      const mockScopedClusterClient = elasticsearchServiceMock.createScopedClusterClient();
+      mockScopedClusterClient.callAsCurrentUser.mockRejectedValue(failureReason);
+      mockOptions.client.asScoped.mockReturnValue(
+        (mockScopedClusterClient as unknown) as jest.Mocked<ScopedClusterClient>
+      );
+
+      const authenticationResult = await provider.authenticate(request);
+
+      expect(authenticationResult.failed()).toBe(true);
+      expect(authenticationResult.error).toBe(failureReason);
+    });
+
+    it('fails if token from `authorization` header is rejected even if state contains a valid one.', async () => {
+      const user = mockAuthenticatedUser();
+      const state = { accessToken: 'token', peerCertificateFingerprint256: '2A:7A:C2:DD' };
+      const request = httpServerMock.createKibanaRequest({
+        headers: { authorization: 'Bearer some-invalid-token' },
+        socket: getMockSocket({
+          authorized: true,
+          peerCertificate: getMockPeerCertificate(state.peerCertificateFingerprint256),
+        }),
+      });
+
+      const failureReason = ElasticsearchErrorHelpers.decorateNotAuthorizedError(new Error());
+      const mockScopedClusterClient = elasticsearchServiceMock.createScopedClusterClient();
+      mockScopedClusterClient.callAsCurrentUser
+        // In response to call with a token from header.
+        .mockRejectedValueOnce(failureReason)
+        // In response to a call with a token from session (not expected to be called).
+        .mockResolvedValueOnce(user);
+      mockOptions.client.asScoped.mockReturnValue(
+        (mockScopedClusterClient as unknown) as jest.Mocked<ScopedClusterClient>
+      );
+
+      const authenticationResult = await provider.authenticate(request, state);
+
+      expect(authenticationResult.failed()).toBe(true);
+      expect(authenticationResult.error).toBe(failureReason);
+    });
+  });
+
+  describe('`logout` method', () => {
+    it('returns `notHandled` if state is not presented.', async () => {
+      const request = httpServerMock.createKibanaRequest();
+
+      let deauthenticateResult = await provider.logout(request);
+      expect(deauthenticateResult.notHandled()).toBe(true);
+
+      deauthenticateResult = await provider.logout(request, null);
+      expect(deauthenticateResult.notHandled()).toBe(true);
+
+      expect(mockOptions.tokens.invalidate).not.toHaveBeenCalled();
+    });
+
+    it('fails if `tokens.invalidate` fails', async () => {
+      const request = httpServerMock.createKibanaRequest();
+      const state = { accessToken: 'foo', peerCertificateFingerprint256: '2A:7A:C2:DD' };
+
+      const failureReason = new Error('failed to delete token');
+      mockOptions.tokens.invalidate.mockRejectedValue(failureReason);
+
+      const authenticationResult = await provider.logout(request, state);
+
+      expect(mockOptions.tokens.invalidate).toHaveBeenCalledTimes(1);
+      expect(mockOptions.tokens.invalidate).toHaveBeenCalledWith({ accessToken: 'foo' });
+
+      expect(authenticationResult.failed()).toBe(true);
+      expect(authenticationResult.error).toBe(failureReason);
+    });
+
+    it('redirects to `/logged_out` page if access token is invalidated successfully.', async () => {
+      const request = httpServerMock.createKibanaRequest();
+      const state = { accessToken: 'foo', peerCertificateFingerprint256: '2A:7A:C2:DD' };
+
+      mockOptions.tokens.invalidate.mockResolvedValue(undefined);
+
+      const authenticationResult = await provider.logout(request, state);
+
+      expect(mockOptions.tokens.invalidate).toHaveBeenCalledTimes(1);
+      expect(mockOptions.tokens.invalidate).toHaveBeenCalledWith({ accessToken: 'foo' });
+
+      expect(authenticationResult.redirected()).toBe(true);
+      expect(authenticationResult.redirectURL).toBe('/logged_out');
+    });
+  });
+});
diff --git a/x-pack/plugins/security/server/authentication/providers/pki.ts b/x-pack/plugins/security/server/authentication/providers/pki.ts
new file mode 100644
index 0000000000000..788395feae442
--- /dev/null
+++ b/x-pack/plugins/security/server/authentication/providers/pki.ts
@@ -0,0 +1,277 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License;
+ * you may not use this file except in compliance with the Elastic License.
+ */
+
+import Boom from 'boom';
+import { DetailedPeerCertificate } from 'tls';
+import { KibanaRequest } from '../../../../../../src/core/server';
+import { AuthenticationResult } from '../authentication_result';
+import { DeauthenticationResult } from '../deauthentication_result';
+import { BaseAuthenticationProvider } from './base';
+import { Tokens } from '../tokens';
+
+/**
+ * The state supported by the provider.
+ */
+interface ProviderState {
+  /**
+   * Access token we got in exchange to peer certificate chain.
+   */
+  accessToken: string;
+
+  /**
+   * The SHA-256 digest of the DER encoded peer leaf certificate. It is a `:` separated hexadecimal string.
+   */
+  peerCertificateFingerprint256: string;
+}
+
+/**
+ * Parses request's `Authorization` HTTP header if present and extracts authentication scheme.
+ * @param request Request instance to extract authentication scheme for.
+ */
+function getRequestAuthenticationScheme(request: KibanaRequest) {
+  const authorization = request.headers.authorization;
+  if (!authorization || typeof authorization !== 'string') {
+    return '';
+  }
+
+  return authorization.split(/\s+/)[0].toLowerCase();
+}
+
+/**
+ * Provider that supports PKI request authentication.
+ */
+export class PKIAuthenticationProvider extends BaseAuthenticationProvider {
+  /**
+   * Performs PKI request authentication.
+   * @param request Request instance.
+   * @param [state] Optional state object associated with the provider.
+   */
+  public async authenticate(request: KibanaRequest, state?: ProviderState | null) {
+    this.logger.debug(`Trying to authenticate user request to ${request.url.path}.`);
+
+    const authenticationScheme = getRequestAuthenticationScheme(request);
+    if (authenticationScheme && authenticationScheme !== 'bearer') {
+      this.logger.debug(`Unsupported authentication scheme: ${authenticationScheme}`);
+      return AuthenticationResult.notHandled();
+    }
+
+    let authenticationResult = AuthenticationResult.notHandled();
+    if (authenticationScheme) {
+      // We should get rid of `Bearer` scheme support as soon as Reporting doesn't need it anymore.
+      authenticationResult = await this.authenticateWithBearerScheme(request);
+    }
+
+    if (state && authenticationResult.notHandled()) {
+      authenticationResult = await this.authenticateViaState(request, state);
+
+      // If access token expired or doesn't match to the certificate fingerprint we should try to get
+      // a new one in exchange to peer certificate chain.
+      if (
+        authenticationResult.notHandled() ||
+        (authenticationResult.failed() &&
+          Tokens.isAccessTokenExpiredError(authenticationResult.error))
+      ) {
+        authenticationResult = await this.authenticateViaPeerCertificate(request);
+        // If we have an active session that we couldn't use to authenticate user and at the same time
+        // we couldn't use peer's certificate to establish a new one, then we should respond with 401
+        // and force authenticator to clear the session.
+        if (authenticationResult.notHandled()) {
+          return AuthenticationResult.failed(Boom.unauthorized());
+        }
+      }
+    }
+
+    // If we couldn't authenticate by means of all methods above, let's try to check if we can authenticate
+    // request using its peer certificate chain, otherwise just return authentication result we have.
+    return authenticationResult.notHandled()
+      ? await this.authenticateViaPeerCertificate(request)
+      : authenticationResult;
+  }
+
+  /**
+   * Invalidates access token retrieved in exchange for peer certificate chain if it exists.
+   * @param request Request instance.
+   * @param state State value previously stored by the provider.
+   */
+  public async logout(request: KibanaRequest, state?: ProviderState | null) {
+    this.logger.debug(`Trying to log user out via ${request.url.path}.`);
+
+    if (!state) {
+      this.logger.debug('There is no access token to invalidate.');
+      return DeauthenticationResult.notHandled();
+    }
+
+    try {
+      await this.options.tokens.invalidate({ accessToken: state.accessToken });
+    } catch (err) {
+      this.logger.debug(`Failed invalidating access token: ${err.message}`);
+      return DeauthenticationResult.failed(err);
+    }
+
+    return DeauthenticationResult.redirectTo('/logged_out');
+  }
+
+  /**
+   * Tries to authenticate request with `Bearer ***` Authorization header by passing it to the Elasticsearch backend.
+   * @param request Request instance.
+   */
+  private async authenticateWithBearerScheme(request: KibanaRequest) {
+    this.logger.debug('Trying to authenticate request using "Bearer" authentication scheme.');
+
+    try {
+      const user = await this.getUser(request);
+
+      this.logger.debug('Request has been authenticated using "Bearer" authentication scheme.');
+      return AuthenticationResult.succeeded(user);
+    } catch (err) {
+      this.logger.debug(
+        `Failed to authenticate request using "Bearer" authentication scheme: ${err.message}`
+      );
+      return AuthenticationResult.failed(err);
+    }
+  }
+
+  /**
+   * Tries to extract access token from state and adds it to the request before it's
+   * forwarded to Elasticsearch backend.
+   * @param request Request instance.
+   * @param state State value previously stored by the provider.
+   */
+  private async authenticateViaState(
+    request: KibanaRequest,
+    { accessToken, peerCertificateFingerprint256 }: ProviderState
+  ) {
+    this.logger.debug('Trying to authenticate via state.');
+
+    // If peer is authorized, but its certificate isn't available, that likely means the connection
+    // with the peer is closed already. We shouldn't invalidate peer's access token in this case
+    // since we cannot guarantee that there is a mismatch in access token and peer certificate.
+    const peerCertificate = request.socket.getPeerCertificate(true);
+    if (peerCertificate === null && request.socket.authorized) {
+      this.logger.debug(
+        'Cannot validate state access token with the peer certificate since it is not available.'
+      );
+      return AuthenticationResult.failed(new Error('Peer certificate is not available'));
+    }
+
+    if (
+      !request.socket.authorized ||
+      peerCertificate === null ||
+      (peerCertificate as any).fingerprint256 !== peerCertificateFingerprint256
+    ) {
+      this.logger.debug(
+        'Peer certificate is not present or its fingerprint does not match to the one associated with the access token. Invalidating access token...'
+      );
+
+      try {
+        await this.options.tokens.invalidate({ accessToken });
+      } catch (err) {
+        this.logger.debug(`Failed to invalidate access token: ${err.message}`);
+        return AuthenticationResult.failed(err);
+      }
+
+      // Return "Not Handled" result to allow provider to try to exchange new peer certificate chain
+      // to the new access token down the line.
+      return AuthenticationResult.notHandled();
+    }
+
+    try {
+      const authHeaders = { authorization: `Bearer ${accessToken}` };
+      const user = await this.getUser(request, authHeaders);
+
+      this.logger.debug('Request has been authenticated via state.');
+      return AuthenticationResult.succeeded(user, { authHeaders });
+    } catch (err) {
+      this.logger.debug(`Failed to authenticate request via state: ${err.message}`);
+      return AuthenticationResult.failed(err);
+    }
+  }
+
+  /**
+   * Tries to exchange peer certificate chain to access/refresh token pair.
+   * @param request Request instance.
+   */
+  private async authenticateViaPeerCertificate(request: KibanaRequest) {
+    this.logger.debug('Trying to authenticate request via peer certificate chain.');
+
+    if (!request.socket.authorized) {
+      this.logger.debug(
+        `Authentication is not possible since peer certificate was not authorized: ${request.socket.authorizationError}.`
+      );
+      return AuthenticationResult.notHandled();
+    }
+
+    const peerCertificate = request.socket.getPeerCertificate(true);
+    if (peerCertificate === null) {
+      this.logger.debug('Authentication is not possible due to missing peer certificate chain.');
+      return AuthenticationResult.notHandled();
+    }
+
+    // We should collect entire certificate chain as an ordered array of certificates encoded as base64 strings.
+    const certificateChain = this.getCertificateChain(peerCertificate);
+    let accessToken: string;
+    try {
+      accessToken = (await this.options.client.callAsInternalUser('shield.delegatePKI', {
+        body: { x509_certificate_chain: certificateChain },
+      })).access_token;
+    } catch (err) {
+      this.logger.debug(
+        `Failed to exchange peer certificate chain to an access token: ${err.message}`
+      );
+      return AuthenticationResult.failed(err);
+    }
+
+    this.logger.debug('Successfully retrieved access token in exchange to peer certificate chain.');
+
+    try {
+      // Then attempt to query for the user details using the new token
+      const authHeaders = { authorization: `Bearer ${accessToken}` };
+      const user = await this.getUser(request, authHeaders);
+
+      this.logger.debug('User has been authenticated with new access token');
+      return AuthenticationResult.succeeded(user, {
+        authHeaders,
+        state: {
+          accessToken,
+          // NodeJS typings don't include `fingerprint256` yet.
+          peerCertificateFingerprint256: (peerCertificate as any).fingerprint256,
+        },
+      });
+    } catch (err) {
+      this.logger.debug(`Failed to authenticate request via access token: ${err.message}`);
+      return AuthenticationResult.failed(err);
+    }
+  }
+
+  /**
+   * Starts from the leaf peer certificate and iterates up to the top-most available certificate
+   * authority using `issuerCertificate` certificate property. THe iteration is stopped only when
+   * we detect circular reference (root/self-signed certificate) or when `issuerCertificate` isn't
+   * available (null or empty object).
+   * @param peerCertificate Peer leaf certificate instance.
+   */
+  private getCertificateChain(peerCertificate: DetailedPeerCertificate | null) {
+    const certificateChain = [];
+    let certificate: DetailedPeerCertificate | null = peerCertificate;
+    while (certificate !== null && Object.keys(certificate).length > 0) {
+      certificateChain.push(certificate.raw.toString('base64'));
+
+      // For self-signed certificates, `issuerCertificate` may be a circular reference.
+      if (certificate === certificate.issuerCertificate) {
+        this.logger.debug('Self-signed certificate is detected in certificate chain');
+        certificate = null;
+      } else {
+        certificate = certificate.issuerCertificate;
+      }
+    }
+
+    this.logger.debug(
+      `Peer certificate chain consists of ${certificateChain.length} certificates.`
+    );
+
+    return certificateChain;
+  }
+}
diff --git a/x-pack/scripts/functional_tests.js b/x-pack/scripts/functional_tests.js
index 222647e000672..f513d117e08ae 100644
--- a/x-pack/scripts/functional_tests.js
+++ b/x-pack/scripts/functional_tests.js
@@ -21,6 +21,7 @@ require('@kbn/test').runTestsCli([
   require.resolve('../test/token_api_integration/config.js'),
   require.resolve('../test/oidc_api_integration/config.ts'),
   require.resolve('../test/oidc_api_integration/implicit_flow.config.ts'),
+  // require.resolve('../test/pki_api_integration/config.ts'),
   require.resolve('../test/spaces_api_integration/spaces_only/config'),
   require.resolve('../test/spaces_api_integration/security_and_spaces/config_trial'),
   require.resolve('../test/spaces_api_integration/security_and_spaces/config_basic'),
diff --git a/x-pack/test/pki_api_integration/apis/index.ts b/x-pack/test/pki_api_integration/apis/index.ts
new file mode 100644
index 0000000000000..d859ed172ac69
--- /dev/null
+++ b/x-pack/test/pki_api_integration/apis/index.ts
@@ -0,0 +1,14 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License;
+ * you may not use this file except in compliance with the Elastic License.
+ */
+
+import { FtrProviderContext } from '../ftr_provider_context';
+
+export default function({ loadTestFile }: FtrProviderContext) {
+  describe('apis PKI', function() {
+    this.tags('ciGroup6');
+    loadTestFile(require.resolve('./security'));
+  });
+}
diff --git a/x-pack/test/pki_api_integration/apis/security/index.ts b/x-pack/test/pki_api_integration/apis/security/index.ts
new file mode 100644
index 0000000000000..d2bfe613ca7fa
--- /dev/null
+++ b/x-pack/test/pki_api_integration/apis/security/index.ts
@@ -0,0 +1,13 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License;
+ * you may not use this file except in compliance with the Elastic License.
+ */
+
+import { FtrProviderContext } from '../../ftr_provider_context';
+
+export default function({ loadTestFile }: FtrProviderContext) {
+  describe('security', () => {
+    loadTestFile(require.resolve('./pki_auth'));
+  });
+}
diff --git a/x-pack/test/pki_api_integration/apis/security/pki_auth.ts b/x-pack/test/pki_api_integration/apis/security/pki_auth.ts
new file mode 100644
index 0000000000000..8c29db674aaf3
--- /dev/null
+++ b/x-pack/test/pki_api_integration/apis/security/pki_auth.ts
@@ -0,0 +1,370 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License;
+ * you may not use this file except in compliance with the Elastic License.
+ */
+
+import expect from '@kbn/expect';
+import request, { Cookie } from 'request';
+import { delay } from 'bluebird';
+import { readFileSync } from 'fs';
+import { resolve } from 'path';
+// @ts-ignore
+import { CA_CERT_PATH } from '@kbn/dev-utils';
+import { FtrProviderContext } from '../../ftr_provider_context';
+
+const CA_CERT = readFileSync(CA_CERT_PATH);
+const FIRST_CLIENT_CERT = readFileSync(resolve(__dirname, '../../fixtures/first_client.p12'));
+const SECOND_CLIENT_CERT = readFileSync(resolve(__dirname, '../../fixtures/second_client.p12'));
+const UNTRUSTED_CLIENT_CERT = readFileSync(
+  resolve(__dirname, '../../fixtures/untrusted_client.p12')
+);
+
+export default function({ getService }: FtrProviderContext) {
+  const supertest = getService('supertestWithoutAuth');
+  const config = getService('config');
+
+  function checkCookieIsSet(cookie: Cookie) {
+    expect(cookie.value).to.not.be.empty();
+
+    expect(cookie.key).to.be('sid');
+    expect(cookie.path).to.be('/');
+    expect(cookie.httpOnly).to.be(true);
+    expect(cookie.maxAge).to.be(null);
+  }
+
+  function checkCookieIsCleared(cookie: Cookie) {
+    expect(cookie.value).to.be.empty();
+
+    expect(cookie.key).to.be('sid');
+    expect(cookie.path).to.be('/');
+    expect(cookie.httpOnly).to.be(true);
+    expect(cookie.maxAge).to.be(0);
+  }
+
+  describe('PKI authentication', () => {
+    before(async () => {
+      await getService('esSupertest')
+        .post('/_security/role_mapping/first_client_pki')
+        .ca(CA_CERT)
+        .send({
+          roles: ['kibana_user'],
+          enabled: true,
+          rules: { field: { dn: 'CN=first_client' } },
+        })
+        .expect(200);
+    });
+
+    it('should reject API requests that use untrusted certificate', async () => {
+      await supertest
+        .get('/api/security/v1/me')
+        .ca(CA_CERT)
+        .pfx(UNTRUSTED_CLIENT_CERT)
+        .set('kbn-xsrf', 'xxx')
+        .expect(401);
+    });
+
+    it('does not prevent basic login', async () => {
+      const [username, password] = config.get('servers.elasticsearch.auth').split(':');
+      const response = await supertest
+        .post('/api/security/v1/login')
+        .ca(CA_CERT)
+        .pfx(UNTRUSTED_CLIENT_CERT)
+        .set('kbn-xsrf', 'xxx')
+        .send({ username, password })
+        .expect(204);
+
+      const cookies = response.headers['set-cookie'];
+      expect(cookies).to.have.length(1);
+
+      const cookie = request.cookie(cookies[0])!;
+      checkCookieIsSet(cookie);
+
+      const { body: user } = await supertest
+        .get('/api/security/v1/me')
+        .ca(CA_CERT)
+        .pfx(UNTRUSTED_CLIENT_CERT)
+        .set('kbn-xsrf', 'xxx')
+        .set('Cookie', cookie.cookieString())
+        .expect(200);
+
+      expect(user.username).to.eql(username);
+      expect(user.authentication_realm).to.eql({ name: 'reserved', type: 'reserved' });
+    });
+
+    it('should properly set cookie and authenticate user', async () => {
+      const response = await supertest
+        .get('/api/security/v1/me')
+        .ca(CA_CERT)
+        .pfx(FIRST_CLIENT_CERT)
+        .expect(200);
+
+      const cookies = response.headers['set-cookie'];
+      expect(cookies).to.have.length(1);
+
+      const sessionCookie = request.cookie(cookies[0])!;
+      checkCookieIsSet(sessionCookie);
+
+      expect(response.body).to.eql({
+        username: 'first_client',
+        roles: ['kibana_user'],
+        full_name: null,
+        email: null,
+        enabled: true,
+        metadata: {
+          pki_delegated_by_realm: 'reserved',
+          pki_delegated_by_user: 'elastic',
+          pki_dn: 'CN=first_client',
+        },
+        authentication_realm: { name: 'pki1', type: 'pki' },
+        lookup_realm: { name: 'pki1', type: 'pki' },
+      });
+
+      // Cookie should be accepted.
+      await supertest
+        .get('/api/security/v1/me')
+        .ca(CA_CERT)
+        .pfx(FIRST_CLIENT_CERT)
+        .set('Cookie', sessionCookie.cookieString())
+        .expect(200);
+    });
+
+    it('should update session if new certificate is provided', async () => {
+      let response = await supertest
+        .get('/api/security/v1/me')
+        .ca(CA_CERT)
+        .pfx(FIRST_CLIENT_CERT)
+        .expect(200);
+
+      const cookies = response.headers['set-cookie'];
+      expect(cookies).to.have.length(1);
+
+      const sessionCookie = request.cookie(cookies[0])!;
+      checkCookieIsSet(sessionCookie);
+
+      response = await supertest
+        .get('/api/security/v1/me')
+        .ca(CA_CERT)
+        .pfx(SECOND_CLIENT_CERT)
+        .set('Cookie', sessionCookie.cookieString())
+        .expect(200, {
+          username: 'second_client',
+          roles: [],
+          full_name: null,
+          email: null,
+          enabled: true,
+          metadata: {
+            pki_delegated_by_realm: 'reserved',
+            pki_delegated_by_user: 'elastic',
+            pki_dn: 'CN=second_client',
+          },
+          authentication_realm: { name: 'pki1', type: 'pki' },
+          lookup_realm: { name: 'pki1', type: 'pki' },
+        });
+
+      checkCookieIsSet(request.cookie(response.headers['set-cookie'][0])!);
+    });
+
+    it('should reject valid cookie if used with untrusted certificate', async () => {
+      const response = await supertest
+        .get('/api/security/v1/me')
+        .ca(CA_CERT)
+        .pfx(FIRST_CLIENT_CERT)
+        .expect(200);
+
+      const cookies = response.headers['set-cookie'];
+      expect(cookies).to.have.length(1);
+
+      const sessionCookie = request.cookie(cookies[0])!;
+      checkCookieIsSet(sessionCookie);
+
+      await supertest
+        .get('/api/security/v1/me')
+        .ca(CA_CERT)
+        .pfx(UNTRUSTED_CLIENT_CERT)
+        .set('Cookie', sessionCookie.cookieString())
+        .expect(401);
+    });
+
+    describe('API access with active session', () => {
+      let sessionCookie: Cookie;
+
+      beforeEach(async () => {
+        const response = await supertest
+          .get('/api/security/v1/me')
+          .ca(CA_CERT)
+          .pfx(FIRST_CLIENT_CERT)
+          .expect(200);
+
+        const cookies = response.headers['set-cookie'];
+        expect(cookies).to.have.length(1);
+
+        sessionCookie = request.cookie(cookies[0])!;
+        checkCookieIsSet(sessionCookie);
+      });
+
+      it('should extend cookie on every successful non-system API call', async () => {
+        const apiResponseOne = await supertest
+          .get('/api/security/v1/me')
+          .ca(CA_CERT)
+          .pfx(FIRST_CLIENT_CERT)
+          .set('kbn-xsrf', 'xxx')
+          .set('Cookie', sessionCookie.cookieString())
+          .expect(200);
+
+        expect(apiResponseOne.headers['set-cookie']).to.not.be(undefined);
+        const sessionCookieOne = request.cookie(apiResponseOne.headers['set-cookie'][0])!;
+
+        checkCookieIsSet(sessionCookieOne);
+        expect(sessionCookieOne.value).to.not.equal(sessionCookie.value);
+
+        const apiResponseTwo = await supertest
+          .get('/api/security/v1/me')
+          .ca(CA_CERT)
+          .pfx(FIRST_CLIENT_CERT)
+          .set('kbn-xsrf', 'xxx')
+          .set('Cookie', sessionCookie.cookieString())
+          .expect(200);
+
+        expect(apiResponseTwo.headers['set-cookie']).to.not.be(undefined);
+        const sessionCookieTwo = request.cookie(apiResponseTwo.headers['set-cookie'][0])!;
+
+        checkCookieIsSet(sessionCookieTwo);
+        expect(sessionCookieTwo.value).to.not.equal(sessionCookieOne.value);
+      });
+
+      it('should not extend cookie for system API calls', async () => {
+        const systemAPIResponse = await supertest
+          .get('/api/security/v1/me')
+          .ca(CA_CERT)
+          .pfx(FIRST_CLIENT_CERT)
+          .set('kbn-xsrf', 'xxx')
+          .set('kbn-system-api', 'true')
+          .set('Cookie', sessionCookie.cookieString())
+          .expect(200);
+
+        expect(systemAPIResponse.headers['set-cookie']).to.be(undefined);
+      });
+
+      it('should fail and preserve session cookie if unsupported authentication schema is used', async () => {
+        const apiResponse = await supertest
+          .get('/api/security/v1/me')
+          .ca(CA_CERT)
+          .pfx(FIRST_CLIENT_CERT)
+          .set('kbn-xsrf', 'xxx')
+          .set('Authorization', 'Basic a3JiNTprcmI1')
+          .set('Cookie', sessionCookie.cookieString())
+          .expect(401);
+
+        expect(apiResponse.headers['set-cookie']).to.be(undefined);
+      });
+    });
+
+    describe('logging out', () => {
+      it('should redirect to `logged_out` page after successful logout', async () => {
+        // First authenticate user to retrieve session cookie.
+        const response = await supertest
+          .get('/api/security/v1/me')
+          .ca(CA_CERT)
+          .pfx(FIRST_CLIENT_CERT)
+          .expect(200);
+
+        let cookies = response.headers['set-cookie'];
+        expect(cookies).to.have.length(1);
+
+        const sessionCookie = request.cookie(cookies[0])!;
+        checkCookieIsSet(sessionCookie);
+
+        // And then log user out.
+        const logoutResponse = await supertest
+          .get('/api/security/v1/logout')
+          .ca(CA_CERT)
+          .pfx(FIRST_CLIENT_CERT)
+          .set('Cookie', sessionCookie.cookieString())
+          .expect(302);
+
+        cookies = logoutResponse.headers['set-cookie'];
+        expect(cookies).to.have.length(1);
+        checkCookieIsCleared(request.cookie(cookies[0])!);
+
+        expect(logoutResponse.headers.location).to.be('/logged_out');
+      });
+
+      it('should redirect to home page if session cookie is not provided', async () => {
+        const logoutResponse = await supertest
+          .get('/api/security/v1/logout')
+          .ca(CA_CERT)
+          .pfx(FIRST_CLIENT_CERT)
+          .expect(302);
+
+        expect(logoutResponse.headers['set-cookie']).to.be(undefined);
+        expect(logoutResponse.headers.location).to.be('/');
+      });
+    });
+
+    describe('API access with expired access token.', () => {
+      let sessionCookie: Cookie;
+
+      beforeEach(async () => {
+        const response = await supertest
+          .get('/api/security/v1/me')
+          .ca(CA_CERT)
+          .pfx(FIRST_CLIENT_CERT)
+          .expect(200);
+
+        const cookies = response.headers['set-cookie'];
+        expect(cookies).to.have.length(1);
+
+        sessionCookie = request.cookie(cookies[0])!;
+        checkCookieIsSet(sessionCookie);
+      });
+
+      it('AJAX call should re-acquire token and update existing cookie', async function() {
+        this.timeout(40000);
+
+        // Access token expiration is set to 15s for API integration tests.
+        // Let's wait for 20s to make sure token expires.
+        await delay(20000);
+
+        // This api call should succeed and automatically refresh token. Returned cookie will contain
+        // the new access token.
+        const apiResponse = await supertest
+          .get('/api/security/v1/me')
+          .ca(CA_CERT)
+          .pfx(FIRST_CLIENT_CERT)
+          .set('kbn-xsrf', 'xxx')
+          .set('Cookie', sessionCookie.cookieString())
+          .expect(200);
+
+        const cookies = apiResponse.headers['set-cookie'];
+        expect(cookies).to.have.length(1);
+
+        const refreshedCookie = request.cookie(cookies[0])!;
+        checkCookieIsSet(refreshedCookie);
+      });
+
+      it('non-AJAX call should re-acquire token and update existing cookie', async function() {
+        this.timeout(40000);
+
+        // Access token expiration is set to 15s for API integration tests.
+        // Let's wait for 20s to make sure token expires.
+        await delay(20000);
+
+        // This request should succeed and automatically refresh token. Returned cookie will contain
+        // the new access and refresh token pair.
+        const nonAjaxResponse = await supertest
+          .get('/app/kibana')
+          .ca(CA_CERT)
+          .pfx(FIRST_CLIENT_CERT)
+          .set('Cookie', sessionCookie.cookieString())
+          .expect(200);
+
+        const cookies = nonAjaxResponse.headers['set-cookie'];
+        expect(cookies).to.have.length(1);
+
+        const refreshedCookie = request.cookie(cookies[0])!;
+        checkCookieIsSet(refreshedCookie);
+      });
+    });
+  });
+}
diff --git a/x-pack/test/pki_api_integration/config.ts b/x-pack/test/pki_api_integration/config.ts
new file mode 100644
index 0000000000000..50b41ad251827
--- /dev/null
+++ b/x-pack/test/pki_api_integration/config.ts
@@ -0,0 +1,70 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License;
+ * you may not use this file except in compliance with the Elastic License.
+ */
+
+import { resolve } from 'path';
+import { FtrConfigProviderContext } from '@kbn/test/types/ftr';
+// @ts-ignore
+import { CA_CERT_PATH, ES_KEY_PATH, ES_CERT_PATH } from '@kbn/dev-utils';
+import { services } from './services';
+
+export default async function({ readConfigFile }: FtrConfigProviderContext) {
+  const xPackAPITestsConfig = await readConfigFile(require.resolve('../api_integration/config.js'));
+
+  const servers = {
+    ...xPackAPITestsConfig.get('servers'),
+    elasticsearch: {
+      ...xPackAPITestsConfig.get('servers.elasticsearch'),
+      protocol: 'https',
+    },
+    kibana: {
+      ...xPackAPITestsConfig.get('servers.kibana'),
+      protocol: 'https',
+    },
+  };
+
+  return {
+    testFiles: [require.resolve('./apis')],
+    servers,
+    services,
+    junit: {
+      reportName: 'X-Pack PKI API Integration Tests',
+    },
+
+    esTestCluster: {
+      ...xPackAPITestsConfig.get('esTestCluster'),
+      ssl: true,
+      serverArgs: [
+        ...xPackAPITestsConfig.get('esTestCluster.serverArgs'),
+        'xpack.security.authc.token.enabled=true',
+        'xpack.security.authc.token.timeout=15s',
+        'xpack.security.http.ssl.client_authentication=optional',
+        'xpack.security.http.ssl.verification_mode=certificate',
+        'xpack.security.authc.realms.native.native1.order=0',
+        'xpack.security.authc.realms.pki.pki1.order=1',
+        'xpack.security.authc.realms.pki.pki1.delegation.enabled=true',
+        `xpack.security.authc.realms.pki.pki1.certificate_authorities=${CA_CERT_PATH}`,
+      ],
+    },
+
+    kbnTestServer: {
+      ...xPackAPITestsConfig.get('kbnTestServer'),
+      serverArgs: [
+        ...xPackAPITestsConfig.get('kbnTestServer.serverArgs'),
+        '--server.ssl.enabled=true',
+        `--server.ssl.key=${ES_KEY_PATH}`,
+        `--server.ssl.certificate=${ES_CERT_PATH}`,
+        `--server.ssl.certificateAuthorities=${JSON.stringify([
+          CA_CERT_PATH,
+          resolve(__dirname, './fixtures/kibana_ca.crt'),
+        ])}`,
+        `--server.ssl.clientAuthentication=required`,
+        `--elasticsearch.hosts=${servers.elasticsearch.protocol}://${servers.elasticsearch.hostname}:${servers.elasticsearch.port}`,
+        `--elasticsearch.ssl.certificateAuthorities=${CA_CERT_PATH}`,
+        `--xpack.security.authc.providers=${JSON.stringify(['pki', 'basic'])}`,
+      ],
+    },
+  };
+}
diff --git a/x-pack/test/pki_api_integration/fixtures/README.md b/x-pack/test/pki_api_integration/fixtures/README.md
new file mode 100644
index 0000000000000..0fcbc76183b48
--- /dev/null
+++ b/x-pack/test/pki_api_integration/fixtures/README.md
@@ -0,0 +1,7 @@
+# PKI Fixtures
+
+* `es_ca.key` - the CA key used to sign certificates from @kbn/dev-utils that are used and trusted by test Elasticsearch server.
+* `first_client.p12` and `second_client.p12` - the client certificate bundles signed by `es_ca.key` and hence trusted by
+both test Kibana and Elasticsearch servers.
+* `untrusted_client.p12` - the client certificate bundle trusted by test Kibana server, but not test Elasticsearch test server.
+* `kibana_ca.crt` and `kibana_ca.key` - the CA certificate and key trusted by test Kibana server only.
\ No newline at end of file
diff --git a/x-pack/test/pki_api_integration/fixtures/es_ca.key b/x-pack/test/pki_api_integration/fixtures/es_ca.key
new file mode 100644
index 0000000000000..5428f86851e5a
--- /dev/null
+++ b/x-pack/test/pki_api_integration/fixtures/es_ca.key
@@ -0,0 +1,27 @@
+-----BEGIN RSA PRIVATE KEY-----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+-----END RSA PRIVATE KEY-----
diff --git a/x-pack/test/pki_api_integration/fixtures/first_client.p12 b/x-pack/test/pki_api_integration/fixtures/first_client.p12
new file mode 100644
index 0000000000000..62da80d9ab80e
Binary files /dev/null and b/x-pack/test/pki_api_integration/fixtures/first_client.p12 differ
diff --git a/x-pack/test/pki_api_integration/fixtures/kibana_ca.crt b/x-pack/test/pki_api_integration/fixtures/kibana_ca.crt
new file mode 100644
index 0000000000000..eb57ad45e23dc
--- /dev/null
+++ b/x-pack/test/pki_api_integration/fixtures/kibana_ca.crt
@@ -0,0 +1,19 @@
+-----BEGIN CERTIFICATE-----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+-----END CERTIFICATE-----
diff --git a/x-pack/test/pki_api_integration/fixtures/kibana_ca.key b/x-pack/test/pki_api_integration/fixtures/kibana_ca.key
new file mode 100644
index 0000000000000..7065ce0ce398d
--- /dev/null
+++ b/x-pack/test/pki_api_integration/fixtures/kibana_ca.key
@@ -0,0 +1,27 @@
+-----BEGIN RSA PRIVATE KEY-----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+jqtbNx8OYYF7PVxiuUsZY3sOIZ5b3t9yWeiFwXUCgYB8tcyRGPiaFQ4kKC9Qutl2
+0fNVwoZg6obTRk288XkbgpbwovQWOO9C8fYvoLKlOIsTv6pPmi/0pHI4ke2JCGR1
+r626prIJ/s3UZY3IXBSm+tUkyuu9/pq1kl5VGg9ZuolHq3J6rjiZajKR+qZxXYTL
+X9NQaB7XVBFwrW7/76FzsQKBgCOOVIzkI22AFDjwP7SqM5xFkqgZrM7rMP1AdncQ
+VThFYhJQfMvrtD9s5KzNMVtSBKgN6ToZKl35AveB++wWEAViH0fLmwtEVmI9wuA9
+8CBKKM32EUPyC7Xl5lKrys03DUb5Z4e23AA6xOP4KO3UqI2yNJAwrAeOBbGq9Cak
+4nUNAoGBAKBhG767ePf/5fMrKJnsdxK2+fpP1UglHHTKOxwtLU9xtkUw96g7yzxj
+5ma66yv1QuGIvAmbLVLCI6MmFvXYQmomoRt2KnYEgxjg8jjXXDdoOsNL87t7l0HA
+CviL/UR7ZZV28rp5TmexRworu7hC4qer9NZxqV0a7bOLq0+uVda9
+-----END RSA PRIVATE KEY-----
diff --git a/x-pack/test/pki_api_integration/fixtures/second_client.p12 b/x-pack/test/pki_api_integration/fixtures/second_client.p12
new file mode 100644
index 0000000000000..1c85686cb7b68
Binary files /dev/null and b/x-pack/test/pki_api_integration/fixtures/second_client.p12 differ
diff --git a/x-pack/test/pki_api_integration/fixtures/untrusted_client.p12 b/x-pack/test/pki_api_integration/fixtures/untrusted_client.p12
new file mode 100644
index 0000000000000..1657afed2c58a
Binary files /dev/null and b/x-pack/test/pki_api_integration/fixtures/untrusted_client.p12 differ
diff --git a/x-pack/test/pki_api_integration/ftr_provider_context.d.ts b/x-pack/test/pki_api_integration/ftr_provider_context.d.ts
new file mode 100644
index 0000000000000..e3add3748f56d
--- /dev/null
+++ b/x-pack/test/pki_api_integration/ftr_provider_context.d.ts
@@ -0,0 +1,11 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License;
+ * you may not use this file except in compliance with the Elastic License.
+ */
+
+import { GenericFtrProviderContext } from '@kbn/test/types/ftr';
+
+import { services } from './services';
+
+export type FtrProviderContext = GenericFtrProviderContext<typeof services, {}>;
diff --git a/x-pack/test/pki_api_integration/services.ts b/x-pack/test/pki_api_integration/services.ts
new file mode 100644
index 0000000000000..31f58df081ddb
--- /dev/null
+++ b/x-pack/test/pki_api_integration/services.ts
@@ -0,0 +1,12 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License;
+ * you may not use this file except in compliance with the Elastic License.
+ */
+
+import { services as apiIntegrationServices } from '../api_integration/services';
+
+export const services = {
+  esSupertest: apiIntegrationServices.esSupertest,
+  supertestWithoutAuth: apiIntegrationServices.supertestWithoutAuth,
+};