<?php
use Microsoft\Graph\Beta\GraphServiceClient;
use Microsoft\Graph\Beta\Generated\Models\Security\UrlThreatSubmission;
use Microsoft\Graph\Beta\Generated\Models\Security\SubmissionCategory;
$graphServiceClient = new GraphServiceClient($tokenRequestContext, $scopes);
$requestBody = new UrlThreatSubmission();
$requestBody->setOdataType('#microsoft.graph.urlThreatSubmission');
$requestBody->setCategory(new SubmissionCategory('phishing'));
$requestBody->setWebUrl('http://phishing.contoso.com');
$result = $graphServiceClient->security()->threatSubmission()->urlThreats()->post($requestBody)->wait();