diff --git a/core/src/main/java/org/keycloak/OAuth2Constants.java b/core/src/main/java/org/keycloak/OAuth2Constants.java
index 2ef01cbb1f..c73d7dc83e 100644
--- a/core/src/main/java/org/keycloak/OAuth2Constants.java
+++ b/core/src/main/java/org/keycloak/OAuth2Constants.java
@@ -55,6 +55,8 @@ public interface OAuth2Constants {
 
     String IMPLICIT = "implicit";
 
+    String USERNAME="username";
+
     String PASSWORD = "password";
 
     String CLIENT_CREDENTIALS = "client_credentials";
diff --git a/services/src/main/java/org/keycloak/authentication/authenticators/directgrant/ValidateOTP.java b/services/src/main/java/org/keycloak/authentication/authenticators/directgrant/ValidateOTP.java
index 3e1d949906..ede22e01eb 100755
--- a/services/src/main/java/org/keycloak/authentication/authenticators/directgrant/ValidateOTP.java
+++ b/services/src/main/java/org/keycloak/authentication/authenticators/directgrant/ValidateOTP.java
@@ -60,6 +60,9 @@ public class ValidateOTP extends AbstractDirectGrantAuthenticator implements Cre
 
         String otp = inputData.getFirst("otp");
 
+        // KEYCLOAK-12908 Backwards compatibility. If paramter "otp" is null, then assign "totp".
+        otp = (otp == null) ? inputData.getFirst("totp") : otp;
+
         // Always use default OTP credential in case of direct grant authentication
         String credentialId = getCredentialProvider(context.getSession())
                     .getDefaultCredential(context.getSession(), context.getRealm(), context.getUser()).getId();
diff --git a/testsuite/integration-arquillian/tests/base/src/test/java/org/keycloak/testsuite/forms/LoginTotpTest.java b/testsuite/integration-arquillian/tests/base/src/test/java/org/keycloak/testsuite/forms/LoginTotpTest.java
index 0a4b17f29e..37761ce059 100644
--- a/testsuite/integration-arquillian/tests/base/src/test/java/org/keycloak/testsuite/forms/LoginTotpTest.java
+++ b/testsuite/integration-arquillian/tests/base/src/test/java/org/keycloak/testsuite/forms/LoginTotpTest.java
@@ -21,7 +21,9 @@ import org.junit.Assert;
 import org.junit.Before;
 import org.junit.Rule;
 import org.junit.Test;
+import org.keycloak.OAuth2Constants;
 import org.keycloak.events.Details;
+import org.keycloak.models.Constants;
 import org.keycloak.models.utils.TimeBasedOTP;
 import org.keycloak.representations.idm.RealmRepresentation;
 import org.keycloak.representations.idm.UserRepresentation;
@@ -32,11 +34,21 @@ import org.keycloak.testsuite.pages.AppPage.RequestType;
 import org.keycloak.testsuite.pages.LoginPage;
 import org.keycloak.testsuite.pages.LoginTotpPage;
 import org.keycloak.testsuite.util.GreenMailRule;
+import org.keycloak.testsuite.util.OAuthClient;
 import org.keycloak.testsuite.util.RealmRepUtil;
 import org.keycloak.testsuite.util.UserBuilder;
 
+import javax.ws.rs.client.Client;
+import javax.ws.rs.client.ClientBuilder;
+import javax.ws.rs.client.Entity;
+import javax.ws.rs.client.WebTarget;
+import javax.ws.rs.core.Form;
+import javax.ws.rs.core.Response;
+import java.io.IOException;
 import java.net.MalformedURLException;
 
+import static org.keycloak.testsuite.auth.page.AuthRealm.TEST;
+
 /**
  * @author <a href="mailto:sthorger@redhat.com">Stian Thorgersen</a>
  * @author Stan Silvert ssilvert@redhat.com (C) 2016 Red Hat Inc.
@@ -182,4 +194,38 @@ public class LoginTotpTest extends AbstractTestRealmKeycloakTest {
 
         loginPage.assertCurrent();
     }
+
+    //KEYCLOAK-12908
+    @Test
+    public void loginWithTotp_getToken_checkCompatibilityCLI() throws IOException {
+        Client httpClient = ClientBuilder.newClient();
+        try {
+            WebTarget exchangeUrl = httpClient.target(OAuthClient.AUTH_SERVER_ROOT)
+                    .path("/realms")
+                    .path(TEST)
+                    .path("protocol/openid-connect/token");
+
+            Form form = new Form()
+                    .param(OAuth2Constants.GRANT_TYPE, OAuth2Constants.PASSWORD)
+                    .param(OAuth2Constants.USERNAME, "test-user@localhost")
+                    .param(OAuth2Constants.PASSWORD, "password")
+                    .param(OAuth2Constants.CLIENT_ID, Constants.ADMIN_CLI_CLIENT_ID);
+
+            // Compatibility between "otp" and "totp"
+            Response response = exchangeUrl.request()
+                    .post(Entity.form(form.param("otp", totp.generateTOTP("totpSecret"))));
+
+            Assert.assertEquals(200, response.getStatus());
+            response.close();
+
+            response = exchangeUrl.request()
+                    .post(Entity.form(form.param("totp", totp.generateTOTP("totpSecret"))));
+
+            Assert.assertEquals(200, response.getStatus());
+            response.close();
+
+        } finally {
+            httpClient.close();
+        }
+    }
 }