/usr/share/php/Symfony/Component/Security/Core/User/ is in php-symfony-security-core 3.4.6+dfsg-1.
This file is owned by root:root, with mode 0o755.
..
/usr/share/php/Symfony/Component/Security/Core/User/AdvancedUserInterface.php
/usr/share/php/Symfony/Component/Security/Core/User/ChainUserProvider.php
/usr/share/php/Symfony/Component/Security/Core/User/EquatableInterface.php
/usr/share/php/Symfony/Component/Security/Core/User/InMemoryUserProvider.php
/usr/share/php/Symfony/Component/Security/Core/User/LdapUserProvider.php
/usr/share/php/Symfony/Component/Security/Core/User/User.php
/usr/share/php/Symfony/Component/Security/Core/User/UserChecker.php
/usr/share/php/Symfony/Component/Security/Core/User/UserCheckerInterface.php
/usr/share/php/Symfony/Component/Security/Core/User/UserInterface.php
/usr/share/php/Symfony/Component/Security/Core/User/UserProviderInterface.php