/usr/share/php/Symfony/Component/Security/vendor/paragonie/ is in php-symfony-security 2.3.21+dfsg-4+deb8u3.
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/usr/share/php/Symfony/Component/Security/vendor/paragonie/random_compat/
/usr/share/php/Symfony/Component/Security/vendor/paragonie/random_compat/lib/
/usr/share/php/Symfony/Component/Security/vendor/paragonie/random_compat/lib/byte_safe_strings.php
/usr/share/php/Symfony/Component/Security/vendor/paragonie/random_compat/lib/cast_to_int.php
/usr/share/php/Symfony/Component/Security/vendor/paragonie/random_compat/lib/error_polyfill.php
/usr/share/php/Symfony/Component/Security/vendor/paragonie/random_compat/lib/random.php
/usr/share/php/Symfony/Component/Security/vendor/paragonie/random_compat/lib/random_bytes_com_dotnet.php
/usr/share/php/Symfony/Component/Security/vendor/paragonie/random_compat/lib/random_bytes_dev_urandom.php
/usr/share/php/Symfony/Component/Security/vendor/paragonie/random_compat/lib/random_bytes_libsodium.php
/usr/share/php/Symfony/Component/Security/vendor/paragonie/random_compat/lib/random_bytes_libsodium_legacy.php
/usr/share/php/Symfony/Component/Security/vendor/paragonie/random_compat/lib/random_bytes_mcrypt.php
/usr/share/php/Symfony/Component/Security/vendor/paragonie/random_compat/lib/random_bytes_openssl.php
/usr/share/php/Symfony/Component/Security/vendor/paragonie/random_compat/lib/random_int.php