/usr/share/php/Symfony/Bundle/SecurityBundle/DependencyInjection/Security/Factory/ is in php-symfony-security-bundle 2.7.10-0ubuntu2.
This file is owned by root:root, with mode 0o755.
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/usr/share/php/Symfony/Bundle/SecurityBundle/DependencyInjection/Security/Factory/AbstractFactory.php
/usr/share/php/Symfony/Bundle/SecurityBundle/DependencyInjection/Security/Factory/FormLoginFactory.php
/usr/share/php/Symfony/Bundle/SecurityBundle/DependencyInjection/Security/Factory/HttpBasicFactory.php
/usr/share/php/Symfony/Bundle/SecurityBundle/DependencyInjection/Security/Factory/HttpDigestFactory.php
/usr/share/php/Symfony/Bundle/SecurityBundle/DependencyInjection/Security/Factory/RememberMeFactory.php
/usr/share/php/Symfony/Bundle/SecurityBundle/DependencyInjection/Security/Factory/RemoteUserFactory.php
/usr/share/php/Symfony/Bundle/SecurityBundle/DependencyInjection/Security/Factory/SecurityFactoryInterface.php
/usr/share/php/Symfony/Bundle/SecurityBundle/DependencyInjection/Security/Factory/SimpleFormFactory.php
/usr/share/php/Symfony/Bundle/SecurityBundle/DependencyInjection/Security/Factory/SimplePreAuthenticationFactory.php
/usr/share/php/Symfony/Bundle/SecurityBundle/DependencyInjection/Security/Factory/X509Factory.php