diff --git a/datamodels/2.x/itop-portal-base/portal/src/Form/ObjectFormManager.php b/datamodels/2.x/itop-portal-base/portal/src/Form/ObjectFormManager.php
index 3fac09f48..2705b8c4d 100644
--- a/datamodels/2.x/itop-portal-base/portal/src/Form/ObjectFormManager.php
+++ b/datamodels/2.x/itop-portal-base/portal/src/Form/ObjectFormManager.php
@@ -91,26 +91,34 @@ class ObjectFormManager extends FormManager
 	 * - formmode : view|edit|create
 	 * - values for parent
 	 *
+	 * @param bool $bTrustContent if false then won't allow TWIG content
+	 *
 	 * @inheritDoc
 	 * @throws \Exception
+	 * @throws \SecurityException if twig content is present and $bTrustContent is false
 	 */
-	static function FromJSON($sJson)
+	public static function FromJSON($sJson, $bTrustContent = false)
 	{
-		if (is_array($sJson))
-		{
+		if (is_array($sJson)) {
 			$aJson = $sJson;
-		}
-		else
-		{
+		} else {
 			$aJson = json_decode($sJson, true);
 		}
 
+		if (false === $bTrustContent) {
+			/** @noinspection NestedPositiveIfStatementsInspection */
+			if (isset($aJson['formproperties']['layout']['type']) && ($aJson['formproperties']['layout']['type'] === 'twig')) {
+				// There will be an IssueLog above in the hierarchy due to the exception, but we are logging here so that we can output the JSON data !
+				IssueLog::Error('Portal received a query with forbidden twig content!', \LogChannels::PORTAL, ['formmanager_data' => $aJson]);
+				throw new \SecurityException('Twig content not allowed in this context!');
+			}
+		}
+
 		/** @var \Combodo\iTop\Portal\Form\ObjectFormManager $oFormManager */
 		$oFormManager = parent::FromJSON($sJson);
 
 		// Retrieving object to edit
-		if (!isset($aJson['formobject_class']))
-		{
+		if (!isset($aJson['formobject_class'])) {
 			throw new Exception('Object class must be defined in order to generate the form');
 		}
 		$sObjectClass = $aJson['formobject_class'];
@@ -151,14 +159,44 @@ class ObjectFormManager extends FormManager
 		}
 
 		// Retrieving callback urls
-		if (!isset($aJson['formcallbacks']))
-		{
+		if (!isset($aJson['formcallbacks'])) {
 			// TODO
 		}
 
 		return $oFormManager;
 	}
 
+	/**
+	 * @param string $sPostedFormManagerData received data from the browser
+	 * @param array $aOriginalFormProperties data generated server side
+	 *
+	 * @return bool true if the data are identical
+	 *
+	 * @since 2.7.6 3.0.0 N°4384 check formmanager_data
+	 */
+	public static function CanTrustFormLayoutContent($sPostedFormManagerData, $aOriginalFormProperties)
+	{
+		$aPostedFormManagerData = json_decode($sPostedFormManagerData, true);
+		$sPostedFormLayoutType = (isset($aPostedFormManagerData['formproperties']['layout']['type'])) ? $aPostedFormManagerData['formproperties']['layout']['type'] : '';
+
+		if ($sPostedFormLayoutType === 'xhtml') {
+			return true;
+		}
+
+		// we need to parse the content so that autoclose tags are returned correctly (`<div />` => `<div></div>`)
+		$oHtmlDocument = new \DOMDocument();
+
+		$sPostedFormLayoutContent = (isset($aPostedFormManagerData['formproperties']['layout']['content'])) ? $aPostedFormManagerData['formproperties']['layout']['content'] : '';
+		$oHtmlDocument->loadXML('<root>'.$sPostedFormLayoutContent.'</root>');
+		$sPostedFormLayoutRendered = $oHtmlDocument->saveHTML();
+
+		$sOriginalFormLayoutContent = (isset($aOriginalFormProperties['layout']['content'])) ? $aOriginalFormProperties['layout']['content'] : '';
+		$oHtmlDocument->loadXML('<root>'.$sOriginalFormLayoutContent.'</root>');
+		$sOriginalFormLayoutContentRendered = $oHtmlDocument->saveHTML();
+
+		return ($sPostedFormLayoutRendered === $sOriginalFormLayoutContentRendered);
+	}
+
 	/**
 	 *
 	 * @return \Symfony\Component\DependencyInjection\ContainerInterface
diff --git a/datamodels/2.x/itop-portal-base/portal/src/Helper/ObjectFormHandlerHelper.php b/datamodels/2.x/itop-portal-base/portal/src/Helper/ObjectFormHandlerHelper.php
index d114b1b05..ff4fcbd49 100644
--- a/datamodels/2.x/itop-portal-base/portal/src/Helper/ObjectFormHandlerHelper.php
+++ b/datamodels/2.x/itop-portal-base/portal/src/Helper/ObjectFormHandlerHelper.php
@@ -108,10 +108,10 @@ class ObjectFormHandlerHelper
 
 	/**
 	 * @param \Symfony\Component\HttpFoundation\Request $oRequest
-	 * @param string                                    $sMode
-	 * @param string                                    $sObjectClass
-	 * @param string                                    $sObjectId
-	 * @param string                                    $aFormProperties
+	 * @param string $sMode
+	 * @param string $sObjectClass
+	 * @param string $sObjectId
+	 * @param array $aFormProperties
 	 *
 	 * @return array
 	 *
@@ -127,9 +127,10 @@ class ObjectFormHandlerHelper
 		$bModal = ($oRequest->isXmlHttpRequest() && empty($sOperation));
 
 		// - Retrieve form properties
+		$aOriginalFormProperties = ApplicationHelper::GetLoadedFormFromClass($this->aCombodoPortalInstanceConf['forms'], $sObjectClass, $sMode);
 		if ($aFormProperties === null)
 		{
-			$aFormProperties = ApplicationHelper::GetLoadedFormFromClass($this->aCombodoPortalInstanceConf['forms'], $sObjectClass, $sMode);
+			$aFormProperties = $aOriginalFormProperties;
 		}
 
 		// - Create and
@@ -281,27 +282,24 @@ class ObjectFormHandlerHelper
 
 			$oFormManager->Build();
 			$aFormData['hidden_fields'] = $oFormManager->GetHiddenFieldsId();
-				// Check the number of editable fields
+			// Check the number of editable fields
 			$aFormData['editable_fields_count'] = $oFormManager->GetForm()->GetEditableFieldCount();
-		}
-		else
-		{
+		} else {
 			// Update / Submit / Cancel
+			/** @var \Combodo\iTop\Portal\Form\ObjectFormManager $sFormManagerClass */
 			$sFormManagerClass = $this->oRequestManipulator->ReadParam('formmanager_class', '', FILTER_UNSAFE_RAW);
 			$sFormManagerData = $this->oRequestManipulator->ReadParam('formmanager_data', '', FILTER_UNSAFE_RAW);
-			if (empty($sFormManagerClass) || empty($sFormManagerData))
-			{
+			if (empty($sFormManagerClass) || empty($sFormManagerData)) {
 				IssueLog::Error(__METHOD__.' at line '.__LINE__.' : Parameters formmanager_class and formamanager_data must be defined.');
 				throw new HttpException(Response::HTTP_INTERNAL_SERVER_ERROR, 'Parameters formmanager_class and formmanager_data must be defined.');
 			}
 
-			/** @var \Combodo\iTop\Portal\Form\ObjectFormManager $oFormManager */
-			$oFormManager = $sFormManagerClass::FromJSON($sFormManagerData);
+			$bTrustContent = $sFormManagerClass::CanTrustFormLayoutContent($sFormManagerData, $aOriginalFormProperties);
+			$oFormManager = $sFormManagerClass::FromJSON($sFormManagerData, $bTrustContent);
 			$oFormManager->SetContainer($this->oContainer);
 
 			// Applying action rules if present
-			if (($oFormManager->GetActionRulesToken() !== null) && ($oFormManager->GetActionRulesToken() !== ''))
-			{
+			if (($oFormManager->GetActionRulesToken() !== null) && ($oFormManager->GetActionRulesToken() !== '')) {
 				$aActionRules = ContextManipulatorHelper::DecodeRulesToken($oFormManager->GetActionRulesToken());
 				$oObj = $oFormManager->GetObject();
 				$this->oContextManipulator->PrepareObject($aActionRules, $oObj);
diff --git a/sources/form/formmanager.class.inc.php b/sources/form/formmanager.class.inc.php
index feeb2359e..4f20d1f4c 100644
--- a/sources/form/formmanager.class.inc.php
+++ b/sources/form/formmanager.class.inc.php
@@ -40,7 +40,8 @@ abstract class FormManager
 	 * - formrenderer_class : The class of the FormRenderer to use in the FormManager
 	 * - formrenderer_endpoint : The endpoint of the renderer
 	 *
-	 * @param string $sJson
+	 * @param string|string[] $sJson
+	 *
 	 * @return $this
 	 */
 	static function FromJSON($sJson)