/usr/share/php/Symfony/Component/Security/Core/Authentication/ is in php-symfony-security 2.3.21+dfsg-4+deb8u3.
This file is owned by root:root, with mode 0o755.
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/usr/share/php/Symfony/Component/Security/Core/Authentication/AuthenticationManagerInterface.php
/usr/share/php/Symfony/Component/Security/Core/Authentication/AuthenticationProviderManager.php
/usr/share/php/Symfony/Component/Security/Core/Authentication/AuthenticationTrustResolver.php
/usr/share/php/Symfony/Component/Security/Core/Authentication/AuthenticationTrustResolverInterface.php
/usr/share/php/Symfony/Component/Security/Core/Authentication/Provider/
/usr/share/php/Symfony/Component/Security/Core/Authentication/Provider/AnonymousAuthenticationProvider.php
/usr/share/php/Symfony/Component/Security/Core/Authentication/Provider/AuthenticationProviderInterface.php
/usr/share/php/Symfony/Component/Security/Core/Authentication/Provider/DaoAuthenticationProvider.php
/usr/share/php/Symfony/Component/Security/Core/Authentication/Provider/PreAuthenticatedAuthenticationProvider.php
/usr/share/php/Symfony/Component/Security/Core/Authentication/Provider/RememberMeAuthenticationProvider.php
/usr/share/php/Symfony/Component/Security/Core/Authentication/Provider/UserAuthenticationProvider.php
/usr/share/php/Symfony/Component/Security/Core/Authentication/RememberMe/
/usr/share/php/Symfony/Component/Security/Core/Authentication/RememberMe/InMemoryTokenProvider.php
/usr/share/php/Symfony/Component/Security/Core/Authentication/RememberMe/PersistentToken.php
/usr/share/php/Symfony/Component/Security/Core/Authentication/RememberMe/PersistentTokenInterface.php
/usr/share/php/Symfony/Component/Security/Core/Authentication/RememberMe/TokenProviderInterface.php
/usr/share/php/Symfony/Component/Security/Core/Authentication/Token/
/usr/share/php/Symfony/Component/Security/Core/Authentication/Token/AbstractToken.php
/usr/share/php/Symfony/Component/Security/Core/Authentication/Token/AnonymousToken.php
/usr/share/php/Symfony/Component/Security/Core/Authentication/Token/PreAuthenticatedToken.php
/usr/share/php/Symfony/Component/Security/Core/Authentication/Token/RememberMeToken.php
/usr/share/php/Symfony/Component/Security/Core/Authentication/Token/TokenInterface.php
/usr/share/php/Symfony/Component/Security/Core/Authentication/Token/UsernamePasswordToken.php