/usr/share/php/Symfony/Component/ is in php-symfony-security-guard 3.4.6+dfsg-1.
This file is owned by root:root, with mode 0o755.
..
/usr/share/php/Symfony/Component/Security/
/usr/share/php/Symfony/Component/Security/Guard/
/usr/share/php/Symfony/Component/Security/Guard/AbstractGuardAuthenticator.php
/usr/share/php/Symfony/Component/Security/Guard/Authenticator/
/usr/share/php/Symfony/Component/Security/Guard/Authenticator/AbstractFormLoginAuthenticator.php
/usr/share/php/Symfony/Component/Security/Guard/AuthenticatorInterface.php
/usr/share/php/Symfony/Component/Security/Guard/Firewall/
/usr/share/php/Symfony/Component/Security/Guard/Firewall/GuardAuthenticationListener.php
/usr/share/php/Symfony/Component/Security/Guard/GuardAuthenticatorHandler.php
/usr/share/php/Symfony/Component/Security/Guard/GuardAuthenticatorInterface.php
/usr/share/php/Symfony/Component/Security/Guard/Provider/
/usr/share/php/Symfony/Component/Security/Guard/Provider/GuardAuthenticationProvider.php
/usr/share/php/Symfony/Component/Security/Guard/Token/
/usr/share/php/Symfony/Component/Security/Guard/Token/GuardTokenInterface.php
/usr/share/php/Symfony/Component/Security/Guard/Token/PostAuthenticationGuardToken.php
/usr/share/php/Symfony/Component/Security/Guard/Token/PreAuthenticationGuardToken.php
/usr/share/php/Symfony/Component/Security/Guard/autoload.php