/usr/share/php/Symfony/Component/HttpKernel/Exception/ is in php-symfony-http-kernel 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/HttpKernel/Exception/AccessDeniedHttpException.php
/usr/share/php/Symfony/Component/HttpKernel/Exception/BadRequestHttpException.php
/usr/share/php/Symfony/Component/HttpKernel/Exception/ConflictHttpException.php
/usr/share/php/Symfony/Component/HttpKernel/Exception/FatalErrorException.php
/usr/share/php/Symfony/Component/HttpKernel/Exception/FlattenException.php
/usr/share/php/Symfony/Component/HttpKernel/Exception/GoneHttpException.php
/usr/share/php/Symfony/Component/HttpKernel/Exception/HttpException.php
/usr/share/php/Symfony/Component/HttpKernel/Exception/HttpExceptionInterface.php
/usr/share/php/Symfony/Component/HttpKernel/Exception/LengthRequiredHttpException.php
/usr/share/php/Symfony/Component/HttpKernel/Exception/MethodNotAllowedHttpException.php
/usr/share/php/Symfony/Component/HttpKernel/Exception/NotAcceptableHttpException.php
/usr/share/php/Symfony/Component/HttpKernel/Exception/NotFoundHttpException.php
/usr/share/php/Symfony/Component/HttpKernel/Exception/PreconditionFailedHttpException.php
/usr/share/php/Symfony/Component/HttpKernel/Exception/PreconditionRequiredHttpException.php
/usr/share/php/Symfony/Component/HttpKernel/Exception/ServiceUnavailableHttpException.php
/usr/share/php/Symfony/Component/HttpKernel/Exception/TooManyRequestsHttpException.php
/usr/share/php/Symfony/Component/HttpKernel/Exception/UnauthorizedHttpException.php
/usr/share/php/Symfony/Component/HttpKernel/Exception/UnsupportedMediaTypeHttpException.php