/usr/share/php/Symfony/Component/Security/Core/User/ is in php-symfony-security 2.7.10-0ubuntu2.
This file is owned by root:root, with mode 0o755.
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/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/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