diff --git a/scripts/install b/scripts/install
index e306a83..9a033a9 100644
--- a/scripts/install
+++ b/scripts/install
@@ -165,6 +165,8 @@ else
 	ynh_app_setting_set --app=$app --key=unprotected_uris --value="/jsonrpc.php"
 fi
 
+ynh_permission_create --permission "ics" --url "/controller=ICalendarController" --allowed "visitors" --label "ICS Public access"
+
 # Calculate and store the config file checksum into the app settings
 ynh_store_file_checksum --file="$final_path/config.php"
 
diff --git a/scripts/upgrade b/scripts/upgrade
index 676f89d..f3a3250 100644
--- a/scripts/upgrade
+++ b/scripts/upgrade
@@ -70,6 +70,11 @@ if ynh_legacy_permissions_exists; then
 	ynh_app_setting_delete --app=$app --key=is_public
 fi
 
+# Create a permission if needed
+if ! ynh_permission_exists --permission="ics"; then
+	ynh_permission_create --permission "ics" --url "/controller=ICalendarController" --allowed "visitors" --label "ICS Public access"
+fi
+
 #=================================================
 # CREATE DEDICATED USER
 #=================================================