diff --git a/drivers/tee/optee/call.c b/drivers/tee/optee/call.c
index fd4beeabd458..c7e25e77222a 100644
--- a/drivers/tee/optee/call.c
+++ b/drivers/tee/optee/call.c
@@ -233,9 +233,13 @@ int optee_open_session(struct tee_context *ctx,
 	msg_arg->params[1].attr = OPTEE_MSG_ATTR_TYPE_VALUE_INPUT |
 				  OPTEE_MSG_ATTR_META;
 	memcpy(&msg_arg->params[0].u.value, arg->uuid, sizeof(arg->uuid));
-	memcpy(&msg_arg->params[1].u.value, arg->uuid, sizeof(arg->clnt_uuid));
 	msg_arg->params[1].u.value.c = arg->clnt_login;
 
+	rc = tee_session_calc_client_uuid((uuid_t *)&msg_arg->params[1].u.value,
+					  arg->clnt_login, arg->clnt_uuid);
+	if (rc)
+		goto out;
+
 	rc = optee_to_msg_param(msg_arg->params + 2, arg->num_params, param);
 	if (rc)
 		goto out;