Tomoyuki Oiwa

フォームから空メール？

意味不明で困っています。

まず使用状況ですがKatzさんの情報を元に、自動返信できるようにした標準のformブロックで問い合わせフォームを設置しています。

しばらく問題なかったのですが、急に「block_form_submission」から中身（メールフォームから送信した場合の、入力してもらう部分の%s）の無いメールが送られてくるようになりました。

concrete5のログを見てもエラーは確認できません。
※送信した履歴はあります。

フォーム一覧→回答を表示　には記載ありませんので、フォームからではなさそうです。（そもそも必須項目を設けているので普通ならフォームから空メールは送れないはず）

これが原因じゃないか？
と何か思い当たる方いらっしゃいませんか？
環境情報も下に記載しておきます。

よろしくお願いいたします。

# concrete5 Version
Core Version - 5.7.5.13
Version Installed - 5.7.5.13
Database Version - 20160615000000

# concrete5 Packages
None

# concrete5 Overrides
blocks/autonav/view.css, blocks/autonav/templates/breadcrumb.php, blocks/autonav/templates/responsive_header_navigation/view.css, blocks/autonav/templates/responsive_header_navigation/view.js, blocks/autonav/templates/responsive_header_navigation/view.php, blocks/autonav/templates/responsive_header_navigation, blocks/autonav/templates, blocks/autonav/view.js, blocks/autonav/view.php, blocks/autonav, blocks/content/view.php, blocks/content/templates/bg_white/view.css, blocks/content/templates/bg_white/view.php, blocks/content/templates/bg_white, blocks/content/templates/cntntsblckl/view.css, blocks/content/templates/cntntsblckl/view.php, blocks/content/templates/cntntsblckl, blocks/content/templates/cntntsblckr/view.css, blocks/content/templates/cntntsblckr/view.php, blocks/content/templates/cntntsblckr, blocks/content/templates/cntntsblckr56/view.css, blocks/content/templates/cntntsblckr56/view.php, blocks/content/templates/cntntsblckr56, blocks/content/templates/tac/view.css, blocks/content/templates/tac/view.php, blocks/content/templates/tac, blocks/content/templates, blocks/content, blocks/btn/add.php, blocks/btn/templates/orange.php, blocks/btn/templates/red.php, blocks/btn/templates, blocks/btn/db.xml, blocks/btn/controller.php, blocks/btn/edit.php, blocks/btn/icon.png, blocks/btn/view.css, blocks/btn/view.php, blocks/btn, blocks/date_navigation/view.css, blocks/date_navigation/view.php, blocks/date_navigation, blocks/external_form/form/controller/contact_form.php, blocks/external_form/form/controller, blocks/external_form/form/contact_form.php, blocks/external_form/form, blocks/external_form, blocks/faq/view.php, blocks/faq, blocks/file/view.php, blocks/file, blocks/form/controller.php, blocks/form/mini_survey.php, blocks/form/view.css, blocks/form/view.php, blocks/form/view.js, blocks/form, blocks/google_map/view.css, blocks/google_map/view.php, blocks/google_map, blocks/page_list/view.css, blocks/page_list/view.php, blocks/page_list, blocks/html/view.php, blocks/html, blocks/image/view.css, blocks/image/templates/mgn0/view.css, blocks/image/templates/mgn0/view.php, blocks/image/templates/mgn0, blocks/image/templates/mgnbtm16/view.css, blocks/image/templates/mgnbtm16/view.php, blocks/image/templates/mgnbtm16, blocks/image/templates/mgnbtm32/view.css, blocks/image/templates/mgnbtm32/view.php, blocks/image/templates/mgnbtm32, blocks/image/templates/circle/view.css, blocks/image/templates/circle/view.php, blocks/image/templates/circle, blocks/image/templates, blocks/image/view.php, blocks/image, blocks/image_banner/add.php, blocks/image_banner/controller.php, blocks/image_banner/composer.php, blocks/image_banner/db.xml, blocks/image_banner/edit.php, blocks/image_banner/icon.png, blocks/image_banner/form_setup_html.php, blocks/image_banner/LICENSE.TXT, blocks/image_banner/view.css, blocks/image_banner/view.php, blocks/image_banner, blocks/horizontal_rule_custom/controller.php, blocks/horizontal_rule_custom/view.css, blocks/horizontal_rule_custom/view.php, blocks/horizontal_rule_custom/icon.png, blocks/horizontal_rule_custom, blocks/youtube/view.css, blocks/youtube/view.php, blocks/youtube, blocks/image_slider/view.css, blocks/image_slider/images/toppilescroll.svg, blocks/image_slider/images, blocks/image_slider/templates/bxslider/view.css, blocks/image_slider/templates/bxslider/images/bx_loader.gif, blocks/image_slider/templates/bxslider/images/controls.png, blocks/image_slider/templates/bxslider/images/nav_prev.png, blocks/image_slider/templates/bxslider/images/nav_next.png, blocks/image_slider/templates/bxslider/images, blocks/image_slider/templates/bxslider/view.php, blocks/image_slider/templates/bxslider/view.js, blocks/image_slider/templates/bxslider, blocks/image_slider/templates, blocks/image_slider/view.js, blocks/image_slider/view.php, blocks/image_slider, blocks/imagecolorbox/add.php, blocks/imagecolorbox/images/controls.png, blocks/imagecolorbox/images/loading_background.png, blocks/imagecolorbox/images/loading.gif, blocks/imagecolorbox/images/overlay.png, blocks/imagecolorbox/images, blocks/imagecolorbox/db.xml, blocks/imagecolorbox/controller.php, blocks/imagecolorbox/edit.php, blocks/imagecolorbox/icon.png, blocks/imagecolorbox/view.css, blocks/imagecolorbox/view.js, blocks/imagecolorbox/view.php, blocks/imagecolorbox, blocks/next_previous/view.css, blocks/next_previous/view.php, blocks/next_previous, blocks/numberlist/add.php, blocks/numberlist/db.xml, blocks/numberlist/controller.php, blocks/numberlist/edit.php, blocks/numberlist/icon.png, blocks/numberlist/form_setup_html.php, blocks/numberlist/view.css, blocks/numberlist/LICENSE.TXT, blocks/numberlist/view.php, blocks/numberlist/templates/list/view.css, blocks/numberlist/templates/list/view.php, blocks/numberlist/templates/list, blocks/numberlist/templates/list_plain/view.css, blocks/numberlist/templates/list_plain/view.php, blocks/numberlist/templates/list_plain, blocks/numberlist/templates, blocks/numberlist, blocks/page_title/templates/archive.php, blocks/page_title/templates/byline.php, blocks/page_title/templates/headertitle.php, blocks/page_title/templates, blocks/page_title, blocks/search/view.css, blocks/search/view.php, blocks/search, blocks/share_this_page/view.php, blocks/share_this_page/view.css, blocks/share_this_page, blocks/table/add.php, blocks/table/templates/blue/view.css, blocks/table/templates/blue/view.php, blocks/table/templates/blue, blocks/table/templates, blocks/table/controller.php, blocks/table/edit.php, blocks/table/db.xml, blocks/table/form_setup_html.php, blocks/table/icon.png, blocks/table/LICENSE.TXT, blocks/table/view.css, blocks/table/view.php, blocks/table, blocks/core_area_layout/view.php, blocks/core_area_layout/controller.php, blocks/core_area_layout, controllers/single_page/dashboard/reports/forms.php, controllers/single_page/dashboard/reports, controllers/single_page/dashboard, controllers/single_page, js/redactor.js, js/responsive-slides.js, languages/cs_CZ/LC_MESSAGES/messages.mo, languages/cs_CZ/LC_MESSAGES, languages/cs_CZ, languages/da_DK/LC_MESSAGES/messages.mo, languages/da_DK/LC_MESSAGES, languages/da_DK, languages/de_DE/LC_MESSAGES/messages.mo, languages/de_DE/LC_MESSAGES, languages/de_DE, languages/el_GR/LC_MESSAGES/messages.mo, languages/el_GR/LC_MESSAGES, languages/el_GR, languages/en_GB/LC_MESSAGES/messages.mo, languages/en_GB/LC_MESSAGES, languages/en_GB, languages/es_PY/LC_MESSAGES/messages.mo, languages/es_PY/LC_MESSAGES, languages/es_PY, languages/fi_FI/LC_MESSAGES/messages.mo, languages/fi_FI/LC_MESSAGES, languages/fi_FI, languages/fr_FR/LC_MESSAGES/messages.mo, languages/fr_FR/LC_MESSAGES, languages/fr_FR, languages/it_IT/LC_MESSAGES/messages.mo, languages/it_IT/LC_MESSAGES, languages/it_IT, languages/ja_JP/LC_MESSAGES/messages.mo, languages/ja_JP/LC_MESSAGES, languages/ja_JP, languages/nl_NL/LC_MESSAGES/messages.mo, languages/nl_NL/LC_MESSAGES, languages/nl_NL, languages/pt_BR/LC_MESSAGES/messages.mo, languages/pt_BR/LC_MESSAGES, languages/pt_BR, languages/ru_RU/LC_MESSAGES/messages.mo, languages/ru_RU/LC_MESSAGES, languages/ru_RU, languages/sv_SE/LC_MESSAGES/messages.mo, languages/sv_SE/LC_MESSAGES, languages/sv_SE, languages/tr_TR/LC_MESSAGES/messages.mo, languages/tr_TR/LC_MESSAGES, languages/tr_TR, mail/block_form_submission_user.php, mail/block_form_submission.php, single_pages/dashboard/reports/forms.php, single_pages/dashboard/reports, single_pages/dashboard, themes/en_graphiction/description.txt, themes/en_graphiction/css/style.css, themes/en_graphiction/css, themes/en_graphiction/elements/footer.php, themes/en_graphiction/elements/header.php, themes/en_graphiction/elements, themes/en_graphiction/js/script.js, themes/en_graphiction/js, themes/en_graphiction/default.php, themes/en_graphiction/full.php, themes/en_graphiction/home.php, themes/en_graphiction/page_forbidden.php, themes/en_graphiction/page_not_found.php, themes/en_graphiction/thumbnail.png, themes/en_graphiction/page_theme.php, themes/en_graphiction/view.php, themes/en_graphiction, blocks/autonav/view.css, blocks/autonav/templates/breadcrumb.php, blocks/autonav/templates/responsive_header_navigation/view.css, blocks/autonav/templates/responsive_header_navigation/view.js, blocks/autonav/templates/responsive_header_navigation/view.php, blocks/autonav/templates/responsive_header_navigation, blocks/autonav/templates, blocks/autonav/view.js, blocks/autonav/view.php, blocks/autonav, blocks/content/view.php, blocks/content/templates/bg_white/view.css, blocks/content/templates/bg_white/view.php, blocks/content/templates/bg_white, blocks/content/templates/cntntsblckl/view.css, blocks/content/templates/cntntsblckl/view.php, blocks/content/templates/cntntsblckl, blocks/content/templates/cntntsblckr/view.css, blocks/content/templates/cntntsblckr/view.php, blocks/content/templates/cntntsblckr, blocks/content/templates/cntntsblckr56/view.css, blocks/content/templates/cntntsblckr56/view.php, blocks/content/templates/cntntsblckr56, blocks/content/templates/tac/view.css, blocks/content/templates/tac/view.php, blocks/content/templates/tac, blocks/content/templates, blocks/content, blocks/btn/add.php, blocks/btn/templates/orange.php, blocks/btn/templates/red.php, blocks/btn/templates, blocks/btn/db.xml, blocks/btn/controller.php, blocks/btn/edit.php, blocks/btn/icon.png, blocks/btn/view.css, blocks/btn/view.php, blocks/btn, blocks/date_navigation/view.css, blocks/date_navigation/view.php, blocks/date_navigation, blocks/external_form/form/controller/contact_form.php, blocks/external_form/form/controller, blocks/external_form/form/contact_form.php, blocks/external_form/form, blocks/external_form, blocks/faq/view.php, blocks/faq, blocks/file/view.php, blocks/file, blocks/form/controller.php, blocks/form/mini_survey.php, blocks/form/view.css, blocks/form/view.php, blocks/form/view.js, blocks/form, blocks/google_map/view.css, blocks/google_map/view.php, blocks/google_map, blocks/page_list/view.css, blocks/page_list/view.php, blocks/page_list, blocks/html/view.php, blocks/html, blocks/image/view.css, blocks/image/templates/mgn0/view.css, blocks/image/templates/mgn0/view.php, blocks/image/templates/mgn0, blocks/image/templates/mgnbtm16/view.css, blocks/image/templates/mgnbtm16/view.php, blocks/image/templates/mgnbtm16, blocks/image/templates/mgnbtm32/view.css, blocks/image/templates/mgnbtm32/view.php, blocks/image/templates/mgnbtm32, blocks/image/templates/circle/view.css, blocks/image/templates/circle/view.php, blocks/image/templates/circle, blocks/image/templates, blocks/image/view.php, blocks/image, blocks/image_banner/add.php, blocks/image_banner/controller.php, blocks/image_banner/composer.php, blocks/image_banner/db.xml, blocks/image_banner/edit.php, blocks/image_banner/icon.png, blocks/image_banner/form_setup_html.php, blocks/image_banner/LICENSE.TXT, blocks/image_banner/view.css, blocks/image_banner/view.php, blocks/image_banner, blocks/horizontal_rule_custom/controller.php, blocks/horizontal_rule_custom/view.css, blocks/horizontal_rule_custom/view.php, blocks/horizontal_rule_custom/icon.png, blocks/horizontal_rule_custom, blocks/youtube/view.css, blocks/youtube/view.php, blocks/youtube, blocks/image_slider/view.css, blocks/image_slider/images/toppilescroll.svg, blocks/image_slider/images, blocks/image_slider/templates/bxslider/view.css, blocks/image_slider/templates/bxslider/images/bx_loader.gif, blocks/image_slider/templates/bxslider/images/controls.png, blocks/image_slider/templates/bxslider/images/nav_prev.png, blocks/image_slider/templates/bxslider/images/nav_next.png, blocks/image_slider/templates/bxslider/images, blocks/image_slider/templates/bxslider/view.php, blocks/image_slider/templates/bxslider/view.js, blocks/image_slider/templates/bxslider, blocks/image_slider/templates, blocks/image_slider/view.js, blocks/image_slider/view.php, blocks/image_slider, blocks/imagecolorbox/add.php, blocks/imagecolorbox/images/controls.png, blocks/imagecolorbox/images/loading_background.png, blocks/imagecolorbox/images/loading.gif, blocks/imagecolorbox/images/overlay.png, blocks/imagecolorbox/images, blocks/imagecolorbox/db.xml, blocks/imagecolorbox/controller.php, blocks/imagecolorbox/edit.php, blocks/imagecolorbox/icon.png, blocks/imagecolorbox/view.css, blocks/imagecolorbox/view.js, blocks/imagecolorbox/view.php, blocks/imagecolorbox, blocks/next_previous/view.css, blocks/next_previous/view.php, blocks/next_previous, blocks/numberlist/add.php, blocks/numberlist/db.xml, blocks/numberlist/controller.php, blocks/numberlist/edit.php, blocks/numberlist/icon.png, blocks/numberlist/form_setup_html.php, blocks/numberlist/view.css, blocks/numberlist/LICENSE.TXT, blocks/numberlist/view.php, blocks/numberlist/templates/list/view.css, blocks/numberlist/templates/list/view.php, blocks/numberlist/templates/list, blocks/numberlist/templates/list_plain/view.css, blocks/numberlist/templates/list_plain/view.php, blocks/numberlist/templates/list_plain, blocks/numberlist/templates, blocks/numberlist, blocks/page_title/templates/archive.php, blocks/page_title/templates/byline.php, blocks/page_title/templates/headertitle.php, blocks/page_title/templates, blocks/page_title, blocks/search/view.css, blocks/search/view.php, blocks/search, blocks/share_this_page/view.php, blocks/share_this_page/view.css, blocks/share_this_page, blocks/table/add.php, blocks/table/templates/blue/view.css, blocks/table/templates/blue/view.php, blocks/table/templates/blue, blocks/table/templates, blocks/table/controller.php, blocks/table/edit.php, blocks/table/db.xml, blocks/table/form_setup_html.php, blocks/table/icon.png, blocks/table/LICENSE.TXT, blocks/table/view.css, blocks/table/view.php, blocks/table, blocks/core_area_layout/view.php, blocks/core_area_layout/controller.php, blocks/core_area_layout, controllers/single_page/dashboard/reports/forms.php, controllers/single_page/dashboard/reports, controllers/single_page/dashboard, controllers/single_page, js/redactor.js, js/responsive-slides.js, languages/cs_CZ/LC_MESSAGES/messages.mo, languages/cs_CZ/LC_MESSAGES, languages/cs_CZ, languages/da_DK/LC_MESSAGES/messages.mo, languages/da_DK/LC_MESSAGES, languages/da_DK, languages/de_DE/LC_MESSAGES/messages.mo, languages/de_DE/LC_MESSAGES, languages/de_DE, languages/el_GR/LC_MESSAGES/messages.mo, languages/el_GR/LC_MESSAGES, languages/el_GR, languages/en_GB/LC_MESSAGES/messages.mo, languages/en_GB/LC_MESSAGES, languages/en_GB, languages/es_PY/LC_MESSAGES/messages.mo, languages/es_PY/LC_MESSAGES, languages/es_PY, languages/fi_FI/LC_MESSAGES/messages.mo, languages/fi_FI/LC_MESSAGES, languages/fi_FI, languages/fr_FR/LC_MESSAGES/messages.mo, languages/fr_FR/LC_MESSAGES, languages/fr_FR, languages/it_IT/LC_MESSAGES/messages.mo, languages/it_IT/LC_MESSAGES, languages/it_IT, languages/ja_JP/LC_MESSAGES/messages.mo, languages/ja_JP/LC_MESSAGES, languages/ja_JP, languages/nl_NL/LC_MESSAGES/messages.mo, languages/nl_NL/LC_MESSAGES, languages/nl_NL, languages/pt_BR/LC_MESSAGES/messages.mo, languages/pt_BR/LC_MESSAGES, languages/pt_BR, languages/ru_RU/LC_MESSAGES/messages.mo, languages/ru_RU/LC_MESSAGES, languages/ru_RU, languages/sv_SE/LC_MESSAGES/messages.mo, languages/sv_SE/LC_MESSAGES, languages/sv_SE, languages/tr_TR/LC_MESSAGES/messages.mo, languages/tr_TR/LC_MESSAGES, languages/tr_TR, mail/block_form_submission_user.php, mail/block_form_submission.php, single_pages/dashboard/reports/forms.php, single_pages/dashboard/reports, single_pages/dashboard, themes/en_graphiction/description.txt, themes/en_graphiction/css/style.css, themes/en_graphiction/css, themes/en_graphiction/elements/footer.php, themes/en_graphiction/elements/header.php, themes/en_graphiction/elements, themes/en_graphiction/js/script.js, themes/en_graphiction/js, themes/en_graphiction/default.php, themes/en_graphiction/full.php, themes/en_graphiction/home.php, themes/en_graphiction/page_forbidden.php, themes/en_graphiction/page_not_found.php, themes/en_graphiction/thumbnail.png, themes/en_graphiction/page_theme.php, themes/en_graphiction/view.php, themes/en_graphiction

# concrete5 Cache Settings
Block Cache - On
Overrides Cache - On
Full Page Caching - On - If blocks on the particular page allow it.
Full Page Cache Lifetime - Every 6 hours (default setting).

# Server Software
Apache/2.2.31

# Server API
cgi-fcgi

# PHP Version
5.6.30

# PHP Extensions
cgi-fcgi, Core, ctype, curl, date, dom, ereg, exif, fileinfo, filter, gd, gettext, gmp, hash, iconv, json, libxml, mbstring, mcrypt, mysql, mysqli, mysqlnd, openssl, pcre, PDO, pdo_mysql, pdo_sqlite, Phar, posix, Reflection, session, SimpleXML, snmp, soap, SPL, sqlite3, standard, tokenizer, xml, xmlreader, xmlwriter, xsl, Zend OPcache, zip, zlib

# PHP Settings
max_execution_time - 30
log_errors_max_len - 1024
max_file_uploads - 20
max_input_nesting_level - 64
max_input_time - -1
max_input_vars - 1000
memory_limit - 1024M
post_max_size - 1023M
sql.safe_mode - Off
upload_max_filesize - 1022M
mysql.max_links - Unlimited
mysql.max_persistent - Unlimited
mysqli.max_links - Unlimited
mysqli.max_persistent - Unlimited
pcre.backtrack_limit - 1000000
pcre.recursion_limit - 100000
session.cache_limiter - no value
session.gc_maxlifetime - 1440
soap.wsdl_cache_limit - 5
opcache.max_accelerated_files - 2000
opcache.max_file_size - 0
opcache.max_wasted_percentage - 5