diff --git a/package_check.sh b/package_check.sh
index af6701d..f91a40c 100755
--- a/package_check.sh
+++ b/package_check.sh
@@ -727,6 +727,10 @@ TEST_RESULTS () {
 		global_level=0
 	fi
 
+	if [ $RESULT_alias_traversal -eq 1 ]
+	then
+		ECHO_FORMAT "Issue alias_traversal was detected ! Please see here https://github.com/YunoHost/example_ynh/pull/45 to fix that.\n" "red" "bold"
+	fi
 
 	# Then, print the levels
 	# Print the global level
@@ -789,6 +793,7 @@ LXC_INIT
 initialize_values() {
 	# Test results
 	RESULT_witness=0
+	RESULT_alias_traversal=0
 	RESULT_linter=0
 	RESULT_global_setup=0
 	RESULT_global_remove=0
diff --git a/sub_scripts/lxc_upgrade.sh b/sub_scripts/lxc_upgrade.sh
index 2b9c822..c7f6577 100755
--- a/sub_scripts/lxc_upgrade.sh
+++ b/sub_scripts/lxc_upgrade.sh
@@ -35,13 +35,13 @@ if [ "$(whoami)" != "$(cat "$script_dir/setup_user")" ] && test -e "$script_dir/
 	exit 0
 fi
 
-echo "\e[1m> Active le bridge réseau\e[0m"
+echo -e "\e[1m> Active le bridge réseau\e[0m"
 if ! sudo ifquery $LXC_BRIDGE --state > /dev/null
 then
 	sudo ifup $LXC_BRIDGE --interfaces=/etc/network/interfaces.d/$LXC_BRIDGE
 fi
 
-echo "\e[1m> Configure le parefeu\e[0m"
+echo -e "\e[1m> Configure le parefeu\e[0m"
 if ! sudo iptables -D FORWARD -i $LXC_BRIDGE -o $main_iface -j ACCEPT 2> /dev/null
 then
 	sudo iptables -A FORWARD -i $LXC_BRIDGE -o $main_iface -j ACCEPT
@@ -55,7 +55,7 @@ then
 	sudo iptables -t nat -A POSTROUTING -s $PLAGE_IP.0/24 -j MASQUERADE
 fi
 
-echo "\e[1m> Démarrage de la machine\e[0m"
+echo -e "\e[1m> Démarrage de la machine\e[0m"
 if [ $(sudo lxc-info --name $LXC_NAME | grep -c "STOPPED") -eq 0 ]; then
 	# Si la machine n'est pas à l'arrêt.
 	sudo lxc-stop -n $LXC_NAME	# Arrête la machine LXC
@@ -67,7 +67,7 @@ sudo lxc-start -n $LXC_NAME -d
 sleep 3
 sudo lxc-ls -f
 
-echo "\e[1m> Update\e[0m"
+echo -e "\e[1m> Update\e[0m"
 update_apt=0
 sudo lxc-attach -n $LXC_NAME -- apt-get update
 sudo lxc-attach -n $LXC_NAME -- apt-get dist-upgrade --dry-run | grep -q "^Inst "	# Vérifie si il y aura des mises à jour.
@@ -75,10 +75,10 @@ sudo lxc-attach -n $LXC_NAME -- apt-get dist-upgrade --dry-run | grep -q "^Inst
 if [ "$?" -eq 0 ]; then
 	update_apt=1
 fi
-echo "\e[1m> Upgrade\e[0m"
+echo -e "\e[1m> Upgrade\e[0m"
 sudo lxc-attach -n $LXC_NAME -- apt-get dist-upgrade --option Dpkg::Options::=--force-confold -yy
 
-echo "\e[1m> Clean\e[0m"
+echo -e "\e[1m> Clean\e[0m"
 sudo lxc-attach -n $LXC_NAME -- apt-get autoremove -y
 sudo lxc-attach -n $LXC_NAME -- apt-get autoclean
 if [ "$update_apt" -eq 1 ]
@@ -86,10 +86,10 @@ then	# Print les numéros de version de Yunohost, si il y a eu un upgrade
 	(sudo lxc-attach -n $LXC_NAME -- yunohost -v) | sudo tee "$script_dir/ynh_version"
 fi
 
-echo "\e[1m> Arrêt de la machine virtualisée\e[0m"
+echo -e "\e[1m> Arrêt de la machine virtualisée\e[0m"
 sudo lxc-stop -n $LXC_NAME
 
-echo "\e[1m> Suppression des règles de parefeu\e[0m"
+echo -e "\e[1m> Suppression des règles de parefeu\e[0m"
 sudo iptables -D FORWARD -i $LXC_BRIDGE -o $main_iface -j ACCEPT
 sudo iptables -D FORWARD -i $main_iface -o $LXC_BRIDGE -j ACCEPT
 sudo iptables -t nat -D POSTROUTING -s $PLAGE_IP.0/24 -j MASQUERADE
@@ -98,9 +98,9 @@ sudo ifdown --force $LXC_BRIDGE
 
 if [ "$update_apt" -eq 1 ]
 then
-	echo "\e[1m> Archivage du snapshot\e[0m"
+	echo -e "\e[1m> Archivage du snapshot\e[0m"
 	sudo tar -cz --acls --xattrs -f /var/lib/lxcsnaps/$LXC_NAME/snap0.tar.gz /var/lib/lxcsnaps/$LXC_NAME/snap0
-	echo "\e[1m> Remplacement du snapshot\e[0m"
+	echo -e "\e[1m> Remplacement du snapshot\e[0m"
 	sudo lxc-snapshot -n $LXC_NAME -d snap0
 	sudo lxc-snapshot -n $LXC_NAME
 fi
diff --git a/sub_scripts/testing_process.sh b/sub_scripts/testing_process.sh
index dbfcb0f..43a7d09 100644
--- a/sub_scripts/testing_process.sh
+++ b/sub_scripts/testing_process.sh
@@ -357,6 +357,11 @@ CHECK_URL () {
 			fi
 		done
 
+		# Detect the issue alias_traversal, https://github.com/yandex/gixy/blob/master/docs/en/plugins/aliastraversal.md
+		curl --location --insecure --silent $check_domain$check_path../html/index.nginx-debian.html \
+			| grep "title" | grep --quiet "Welcome to nginx on Debian" \
+			&& (ECHO_FORMAT "Issue alias_traversal detected ! Please see here https://github.com/YunoHost/example_ynh/pull/45 to fix that.\n" "red" "bold" && RESULT_alias_traversal=1)
+
 		# Remove the entries in /etc/hosts for the test domain
 		sudo sed --in-place '/#package_check/d' /etc/hosts
 	else