Modified files and malicious files

Hello guys,

I got this e-mail and this is a bit alarming. Are all these false positives? Is this happening to more people? I’ve used WordFence for years and always keep my plug-ins and WordPress versions up to date (I update shortly after I get the e-mail announcing updates). Thanks for your help.

Alert generated at Thursday 15th of December 2016 at 11:41:12 AM

HIGH SENSITIVITY scanning is enabled, it may produce false positives
Critical Problems:

* WordPress core file modified: wp-includes/class-http.php

* WordPress core file modified: wp-includes/class-json.php

* WordPress core file modified: wp-includes/class-oembed.php

* WordPress core file modified: wp-includes/class-phpass.php

* WordPress core file modified: wp-includes/class-phpmailer.php

* WordPress core file modified: wp-includes/class-pop3.php

* WordPress core file modified: wp-includes/class-requests.php

* WordPress core file modified: wp-includes/class-smtp.php

* WordPress core file modified: wp-includes/class-snoopy.php

* WordPress core file modified: wp-includes/class-walker-category-dropdown.php

* WordPress core file modified: wp-includes/class-walker-category.php

* WordPress core file modified: wp-includes/class-walker-comment.php

* WordPress core file modified: wp-includes/class-walker-nav-menu.php

* WordPress core file modified: wp-includes/class-walker-page-dropdown.php

* WordPress core file modified: wp-includes/class-walker-page.php

* WordPress core file modified: wp-includes/class-wp-admin-bar.php

* WordPress core file modified: wp-includes/class-wp-ajax-response.php

* WordPress core file modified: wp-includes/class-wp-comment-query.php

* WordPress core file modified: wp-includes/class-wp-comment.php

* WordPress core file modified: wp-includes/class-wp-customize-control.php

* WordPress core file modified: wp-includes/class-wp-customize-nav-menus.php

* WordPress core file modified: wp-includes/class-wp-customize-panel.php

* WordPress core file modified: wp-includes/class-wp-customize-section.php

* WordPress core file modified: wp-includes/class-wp-customize-setting.php

* WordPress core file modified: wp-includes/class-wp-customize-widgets.php

* WordPress core file modified: wp-includes/class-wp-dependency.php

* WordPress core file modified: wp-includes/class-wp-editor.php

* WordPress core file modified: wp-includes/class-wp-embed.php

* WordPress core file modified: wp-includes/class-wp-error.php

* WordPress core file modified: wp-includes/class-wp-feed-cache-transient.php

* WordPress core file modified: wp-includes/class-wp-feed-cache.php

* WordPress core file modified: wp-includes/class-wp-hook.php

* WordPress core file modified: wp-includes/class-wp-http-cookie.php

* WordPress core file modified: wp-includes/class-wp-http-curl.php

* WordPress core file modified: wp-includes/class-wp-http-encoding.php

* WordPress core file modified: wp-includes/class-wp-http-ixr-client.php

* WordPress core file modified: wp-includes/class-wp-http-proxy.php

* WordPress core file modified: wp-includes/class-wp-http-requests-hooks.php

* WordPress core file modified: wp-includes/class-wp-http-requests-response.php

* WordPress core file modified: wp-includes/class-wp-http-response.php

* WordPress core file modified: wp-includes/class-wp-http-streams.php

* WordPress core file modified: wp-includes/class-wp-image-editor-gd.php

* WordPress core file modified: wp-includes/class-wp-image-editor-imagick.php

* WordPress core file modified: wp-includes/class-wp-image-editor.php

* WordPress core file modified: wp-includes/class-wp-list-util.php

* WordPress core file modified: wp-includes/class-wp-locale-switcher.php

* WordPress core file modified: wp-includes/class-wp-locale.php

* WordPress core file modified: wp-includes/class-wp-matchesmapregex.php

* WordPress core file modified: wp-includes/class-wp-meta-query.php

* WordPress core file modified: wp-includes/class-wp-metadata-lazyloader.php

* WordPress core file modified: wp-includes/class-wp-network-query.php

* WordPress core file modified: wp-includes/class-wp-network.php

* WordPress core file modified: wp-includes/class-wp-oembed-controller.php

* WordPress core file modified: wp-includes/class-wp-post-type.php

* WordPress core file modified: wp-includes/class-wp-post.php

* WordPress core file modified: wp-includes/class-wp-query.php

* WordPress core file modified: wp-includes/class-wp-rewrite.php

* WordPress core file modified: wp-includes/class-wp-role.php

* WordPress core file modified: wp-includes/class-wp-roles.php

* WordPress core file modified: wp-includes/class-wp-session-tokens.php

* WordPress core file modified: wp-includes/class-wp-simplepie-file.php

* WordPress core file modified: wp-includes/class-wp-simplepie-sanitize-kses.php

* WordPress core file modified: wp-includes/class-wp-site-query.php

* WordPress core file modified: wp-includes/class-wp-site.php

* WordPress core file modified: wp-includes/class-wp-tax-query.php

* WordPress core file modified: wp-includes/class-wp-taxonomy.php

* WordPress core file modified: wp-includes/class-wp-term-query.php

* WordPress core file modified: wp-includes/class-wp-term.php

* WordPress core file modified: wp-includes/class-wp-text-diff-renderer-inline.php

* WordPress core file modified: wp-includes/class-wp-text-diff-renderer-table.php

* WordPress core file modified: wp-includes/class-wp-theme.php

* WordPress core file modified: wp-includes/class-wp-user-meta-session-tokens.php

* WordPress core file modified: wp-includes/class-wp-user-query.php

* WordPress core file modified: wp-includes/class-wp-user.php

* WordPress core file modified: wp-includes/class-wp-walker.php

* WordPress core file modified: wp-includes/class-wp-widget-factory.php

* WordPress core file modified: wp-includes/class-wp-widget.php

* WordPress core file modified: wp-includes/class-wp-xmlrpc-server.php

* WordPress core file modified: wp-includes/class.wp-dependencies.php

* WordPress core file modified: wp-includes/widgets/class-wp-widget-meta.php

* WordPress core file modified: wp-includes/widgets/class-wp-widget-pages.php

* WordPress core file modified: wp-includes/widgets/class-wp-widget-recent-comments.php

* WordPress core file modified: wp-includes/widgets/class-wp-widget-recent-posts.php

* WordPress core file modified: wp-includes/widgets/class-wp-widget-rss.php

* WordPress core file modified: wp-includes/widgets/class-wp-widget-search.php

* WordPress core file modified: wp-includes/widgets/class-wp-widget-tag-cloud.php

* WordPress core file modified: wp-includes/widgets/class-wp-widget-text.php

* WordPress core file modified: wp-includes/widgets.php

* WordPress core file modified: wp-includes/wp-db.php

* WordPress core file modified: wp-includes/wp-diff.php

* WordPress core file modified: wp-links-opml.php

* WordPress core file modified: wp-load.php

* WordPress core file modified: wp-login.php

* WordPress core file modified: wp-mail.php

* WordPress core file modified: wp-settings.php

* WordPress core file modified: wp-signup.php

* WordPress core file modified: wp-trackback.php

* WordPress core file modified: xmlrpc.php

* File appears to be malicious: wp-content/plugins/contact-form-7/modules/date.php

* File appears to be malicious: wp-content/plugins/wp-smushit/lib/class-wp-smush-resize.php

* File appears to be malicious: wp-content/plugins/w3-total-cache/lib/Microsoft/WindowsAzure/Storage/Batch.php

* File appears to be malicious: wp-includes/SimplePie/Restriction.php

* File appears to be malicious: wp-content/plugins/w3-total-cache/lib/Microsoft/WindowsAzure/Storage/BlobInstance.php

* File appears to be malicious: wp-content/themes/responsive/front-page.php

* File appears to be malicious: wp-admin/widgets.php

* File appears to be malicious: wp-content/plugins/w3-total-cache/lib/Microsoft/Http/Client/Adapter/Socket.php

* File appears to be malicious: wp-content/plugins/w3-total-cache/lib/Google/Http/REST.php

* File appears to be malicious: wp-content/plugins/updraftplus/includes/Dropbox/OAuth/Consumer/ConsumerAbstract.php

* File appears to be malicious: wp-admin/user/user-edit.php

* File appears to be malicious: wp-content/plugins/w3-total-cache/lib/Microsoft/WindowsAzure/Diagnostics/LogLevel.php

* File appears to be malicious: wp-includes/SimplePie/Cache/MySQL.php

* File appears to be malicious: wp-includes/class-walker-page-dropdown.php

* File appears to be malicious: wp-content/plugins/updraftplus/includes/google-extensions.php

* File appears to be malicious: wp-content/plugins/updraftplus/central/modules/updraftplus.php

* File appears to be malicious: wp-includes/class-wp-matchesmapregex.php

* File appears to be malicious: wp-content/plugins/w3-total-cache/lib/Microsoft/Http/Client/Exception.php

* File appears to be malicious: wp-content/plugins/updraftplus/central/modules/updates.php

* File appears to be malicious: wp-includes/class-wp-simplepie-sanitize-kses.php

* File appears to be malicious: wp-content/plugins/w3-total-cache/lib/Google/Http/MediaFileUpload.php

* File appears to be malicious: wp-content/plugins/updraftplus/includes/Google/Logger/Exception.php

* File appears to be malicious: wp-includes/class-http.php

* File appears to be malicious: wp-includes/customize/class-wp-customize-nav-menus-panel.php

* File appears to be malicious: wp-content/plugins/contact-form-7/includes/contact-form.php

* File appears to be malicious: wp-content/plugins/w3-total-cache/lib/Google/Auth/OAuth2.php

* File appears to be malicious: wp-includes/SimplePie/Author.php

* File appears to be malicious: wp-includes/customize/class-wp-customize-site-icon-control.php

* File appears to be malicious: wp-content/plugins/w3-total-cache/lib/Microsoft/WindowsAzure/Storage/Blob.php

* File appears to be malicious: wp-content/plugins/wp-smushit/extras/free-dashboard/module.php

* File appears to be malicious: wp-content/plugins/wp-live-chat-software-for-wordpress/plugin_files/helpers/TrackingCodeInfoHelper.class.php

* File appears to be malicious: wp-content/plugins/updraftplus/includes/phpseclib/Crypt/Random.php

* File appears to be malicious: wp-content/themes/responsive/full-width-page.php

* File appears to be malicious: wp-includes/Requests/Exception/HTTP/502.php

* File appears to be malicious: wp-includes/class-phpass.php

* File appears to be malicious: wp-content/w3tc-config/master.php

* File appears to be malicious: wp-content/plugins/w3-total-cache/lib/Minify/Minify/HTML.php

* File appears to be malicious: wp-content/plugins/w3-total-cache/wp-content/advanced-cache.php

* File appears to be malicious: wp-includes/Requests/Exception/HTTP/413.php

* File appears to be malicious: wp-includes/customize/class-wp-widget-form-customize-control.php

* File appears to be malicious: wp-includes/class-wp-role.php

* File appears to be malicious: wp-content/plugins/w3-total-cache/lib/Microsoft/Http/Exception.php

* File appears to be malicious: wp-admin/theme-install.php

* File appears to be malicious: wp-content/plugins/updraftplus/includes/Dropbox2/OAuth/Storage/WordPress.php

* File appears to be malicious: wp-includes/customize/class-wp-customize-partial.php

* File appears to be malicious: wp-content/themes/responsive/core/includes/functions-extras.php

* File appears to be malicious: wp-includes/customize/class-wp-customize-media-control.php

* File appears to be malicious: wp-content/plugins/updraftplus/includes/Dropbox2/OAuth/Storage/StorageInterface.php

* File appears to be malicious: wp-includes/Requests/Hooker.php

* File appears to be malicious: wp-content/plugins/autoptimize/classes/external/php/minify-css-compressor.php

* File appears to be malicious: wp-content/plugins/contact-form-7/modules/checkbox.php

* File appears to be malicious: wp-includes/class-wp-customize-panel.php

* File appears to be malicious: wp-content/plugins/updraftplus/updraftplus.php

* File appears to be malicious: wp-content/plugins/contact-form-7/uninstall.php

* File appears to be malicious: wp-content/themes/responsive/core/includes/classes/class-tgm-plugin-activation.php

* File appears to be malicious: wp-content/plugins/updraftplus/includes/Google/Auth/LoginTicket.php

* File appears to be malicious: wp-content/plugins/w3-total-cache/lib/Microsoft/WindowsAzure/RetryPolicy/RetryN.php

* File appears to be malicious: wp-content/plugins/wp-smushit/lib/class-wp-smush-settings.php

* File appears to be malicious: wp-includes/pomo/entry.php

* File appears to be malicious: wp-includes/class-walker-category.php

* File appears to be malicious: wp-content/plugins/w3-total-cache/lib/Minify/Minify/Cache/File.php

* File appears to be malicious: wp-content/plugins/updraftplus/includes/Dropbox2/API.php

* File appears to be malicious: wp-includes/class-wp-walker.php

* File appears to be malicious: wp-content/plugins/wp-responsive-menu/inc/includes/class-options-sanitization.php

* File appears to be malicious: wp-content/plugins/w3-total-cache/inc/define.php

* File appears to be malicious: wp-content/plugins/updraftplus/includes/Google/Service/Storage.php

* File appears to be malicious: wp-includes/l10n.php

* File appears to be malicious: wp-includes/Requests/Exception/HTTP/428.php

* File appears to be malicious: wp-content/plugins/w3-total-cache/lib/Minify/HTTP/Encoder.php

* File appears to be malicious: wp-admin/upgrade.php

* File appears to be malicious: wp-content/themes/responsive/header.php

* File appears to be malicious: wp-content/plugins/contact-form-7/modules/file.php

* File appears to be malicious: wp-content/plugins/_qtranslate/qtranslate_hooks.php

* File appears to be malicious: wp-content/plugins/updraftplus/central/classes/class-automatic-upgrader-skin.php

* File appears to be malicious: wp-content/plugins/updraftplus/options.php

* File appears to be malicious: wp-content/plugins/contact-form-7/includes/validation.php

* File appears to be malicious: wp-content/plugins/w3-total-cache/inc/mime/all.php

* File appears to be malicious: wp-includes/SimplePie/File.php

* File appears to be malicious: wp-content/wflogs/ips.php

* File appears to be malicious: wp-content/plugins/w3-total-cache/inc/mime/cssjs.php

* File appears to be malicious: wp-includes/customize/class-wp-customize-nav-menu-section.php

* File appears to be malicious: wp-content/plugins/_qtranslate/qtranslate_javascript.php

* File appears to be malicious: wp-includes/Requests/Exception.php

* File appears to be malicious: wp-content/plugins/w3-total-cache/lib/Google/Verifier/Abstract.php

* File appears to be malicious: wp-content/plugins/w3-total-cache/Support_Page_View_PageContent.php

* File appears to be malicious: wp-includes/customize/class-wp-customize-theme-control.php

* File appears to be malicious: wp-signup.php

* File appears to be malicious: wp-content/plugins/updraftplus/includes/Dropbox2/OAuth/Consumer/Curl.php

* File appears to be malicious: wp-includes/widgets/class-wp-widget-rss.php

* File appears to be malicious: wp-includes/SimplePie/Locator.php

* File appears to be malicious: wp-content/plugins/updraftplus/includes/Google/Exception.php

* File appears to be malicious: wp-includes/rest-api/fields/class-wp-rest-term-meta-fields.php

* File appears to be malicious: wp-content/plugins/wp-smushit/lib/class-wp-smush-async.php

* File appears to be malicious: wp-includes/class-requests.php

* File appears to be malicious: wp-content/plugins/updraftplus/includes/Google/Task/Exception.php

* File appears to be malicious: wp-includes/Requests/Cookie/Jar.php

* File appears to be malicious: wp-content/plugins/wp-live-chat-software-for-wordpress/livechat.php

* File appears to be malicious: wp-includes/class-wp-session-tokens.php

* File appears to be malicious: wp-content/plugins/updraftplus/includes/phpseclib/File/X509.php

* File appears to be malicious: wp-includes/customize/class-wp-customize-nav-menu-control.php

* File appears to be malicious: wp-content/plugins/updraftplus/includes/cloudfiles/cloudfiles_exceptions.php

* File appears to be malicious: wp-content/plugins/updraftplus/includes/Google/Cache/Abstract.php

* File appears to be malicious: wp-content/advanced-cache.php

* File appears to be malicious: wp-includes/functions.php

* File appears to be malicious: wp-includes/class-wp-metadata-lazyloader.php

* File appears to be malicious: wp-content/plugins/contact-form-7/modules/text.php

* File appears to be malicious: wp-includes/class-wp-ajax-response.php

* File appears to be malicious: wp-content/plugins/w3-total-cache/pub/sns.php

* File appears to be malicious: wp-includes/customize/class-wp-customize-nav-menu-setting.php

* File appears to be malicious: wp-content/plugins/autoptimize/config/delayed.php

* File appears to be malicious: wp-content/plugins/autoptimize/classes/autoptimizeToolbar.php

* File appears to be malicious: wp-content/themes/index.php

* File appears to be malicious: wp-content/plugins/p3-profiler/templates/index.php

* File appears to be malicious: wp-includes/ms-blogs.php

* File appears to be malicious: wp-includes/class-wp-user.php

* File appears to be malicious: wp-content/plugins/updraftplus/central/listener.php

* File appears to be malicious: wp-includes/theme-compat/header.php

* File appears to be malicious: wp-content/plugins/cloudflare/index.php

* File appears to be malicious: wp-admin/user-new.php

* File appears to be malicious: wp-includes/Requests/Exception/HTTP/305.php

* File appears to be malicious: wp-includes/Requests/Exception/HTTP/505.php

* File appears to be malicious: wp-admin/update.php

* File appears to be malicious: wp-content/plugins/contact-form-7/modules/hidden.php

* File appears to be malicious: wp-includes/theme-compat/embed-404.php

* File appears to be malicious: wp-content/plugins/p3-profiler/classes/class.p3-profiler-table-sorter.php

* File appears to be malicious: wp-includes/feed-atom-comments.php

* File appears to be malicious: wp-includes/class-pop3.php

* File appears to be malicious: wp-includes/class-wp-hook.php

* File appears to be malicious: wp-includes/Requests/Proxy.php

* File appears to be malicious: wp-content/plugins/contact-form-7/modules/really-simple-captcha.php

* File appears to be malicious: wp-content/plugins/w3-total-cache/lib/NewRelic/NewRelicAPI.php

* File appears to be malicious: wp-content/plugins/updraftplus/templates/wp-admin/advanced/wipe-settings.php

* File appears to be malicious: wp-content/plugins/updraftplus/vendor/rackspace/php-opencloud/lib/php-opencloud.php

* File appears to be malicious: wp-includes/IXR/class-IXR-introspectionserver.php

* File appears to be malicious: wp-content/themes/responsive/blog.php

* File appears to be malicious: wp-content/plugins/updraftplus/admin.php

* File appears to be malicious: wp-content/plugins/updraftplus/templates/wp-admin/notices/report.php

* File appears to be malicious: wp-admin/upload.php

* File appears to be malicious: wp-includes/Text/Diff/Renderer/inline.php

* File appears to be malicious: wp-content/plugins/wp-smushit/lib/wp-async-task.php

* File appears to be malicious: wp-admin/theme-editor.php

* File appears to be malicious: wp-content/wflogs/attack-data.php

* File appears to be malicious: wp-includes/theme-compat/header-embed.php

* File appears to be malicious: wp-includes/widgets/class-wp-widget-links.php

* File appears to be malicious: wp-content/plugins/updraftplus/includes/Google/Service/Dns.php

* File appears to be malicious: wp-content/plugins/p3-profiler/classes/index.php

* File appears to be malicious: wp-content/plugins/w3-total-cache/lib/Google/Cache/File.php

* File appears to be malicious: wp-content/plugins/w3-total-cache/Support_Page_View_DoneContent.php

* File appears to be malicious: wp-content/themes/responsive/core/includes/tha-theme-hooks.php

* File appears to be malicious: wp-content/plugins/contact-form-7/modules/count.php

* File appears to be malicious: wp-includes/wp-diff.php

* File appears to be malicious: wp-includes/Requests/Exception/HTTP/411.php

* File appears to be malicious: wp-includes/media.php

* File appears to be malicious: wp-content/plugins/w3-total-cache/wp-content/object-cache.php

* File appears to be malicious: wp-includes/rewrite.php

* File appears to be malicious: wp-includes/embed-template.php

* File appears to be malicious: wp-includes/Requests/Exception/HTTP/402.php

* File appears to be malicious: wp-content/plugins/updraftplus/restorer.php

* File appears to be malicious: wp-content/plugins/updraftplus/includes/Google/autoload.php

* File appears to be malicious: wp-content/plugins/w3-total-cache/lib/Minify/HTTP/ConditionalGet.php

35 issues were omitted from this email.

Best regards.