{"id":57697,"date":"2026-05-28T04:12:00","date_gmt":"2026-05-28T04:12:00","guid":{"rendered":"https:\/\/zero.redgem.net\/?p=57697"},"modified":"2026-05-28T04:12:00","modified_gmt":"2026-05-28T04:12:00","slug":"appointment-booking-calendar-16118-missing-authorization-to-unauthenticated-arbitrary-modification-v","status":"publish","type":"post","link":"https:\/\/zero.redgem.net\/?p=57697","title":{"rendered":"Appointment Booking Calendar <= 1.6.11.8 - Missing Authorization to Unauthenticated Arbitrary Modification via Bulk Appointments REST API Endpoint_CVE-2026-6937"},"content":{"rendered":"<p>{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;The Appointment Booking Calendar \u2014 Simply Schedule Appointments Booking Plugin plugin for WordPress is vulnerable to Missing Authorization in all versions up to, and including, 1.6.11.8 due to the plugin not properly verifying that a user is authorized to perform an action via the bulk appointments REST API endpoint. 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Endpoint&#8221;,&#8221;source&#8221;:&#8221;Wordfence&#8221;,&#8221;references&#8221;:&#8221;https:\/\/www.wordfence.com\/threat-intel\/vulnerabilities\/id\/ef0f5f9d-788a-4cf8-9747-ada076a69a1f?source=cve\\nhttps:\/\/plugins.trac.wordpress.org\/browser\/simply-schedule-appointments\/trunk\/includes\/class-bootstrap.php#L151\\nhttps:\/\/plugins.trac.wordpress.org\/browser\/simply-schedule-appointments\/trunk\/includes\/lib\/td-util\/class-td-api-model.php#L74\\nhttps:\/\/plugins.trac.wordpress.org\/browser\/simply-schedule-appointments\/tags\/1.6.11.0\/includes\/lib\/td-util\/class-td-api-model.php#L74\\nhttps:\/\/plugins.trac.wordpress.org\/browser\/simply-schedule-appointments\/trunk\/includes\/class-appointment-model.php#L724\\nhttps:\/\/plugins.trac.wordpress.org\/browser\/simply-schedule-appointments\/tags\/1.6.11.0\/includes\/class-appointment-model.php#L724\\nhttps:\/\/plugins.trac.wordpress.org\/browser\/simply-schedule-appointments\/tags\/1.6.11.0\/includes\/class-bootstrap.php#L151\\nhttps:\/\/plugins.trac.wordpress.org\/browser\/simply-schedule-appointments\/tags\/1.6.10.0\/includes\/lib\/td-util\/class-td-api-model.php#L74\\nhttps:\/\/plugins.trac.wordpress.org\/browser\/simply-schedule-appointments\/tags\/1.6.10.0\/includes\/class-appointment-model.php#L724\\nhttps:\/\/plugins.trac.wordpress.org\/browser\/simply-schedule-appointments\/tags\/1.6.10.0\/includes\/class-bootstrap.php#L151\\nhttps:\/\/plugins.trac.wordpress.org\/changeset?sfp_email=\\u0026sfph_mail=\\u0026reponame=\\u0026old=3549843%40simply-schedule-appointments\\u0026new=3549843%40simply-schedule-appointments\\u0026sfp_email=\\u0026sfph_mail=&#8221;,&#8221;id&#8221;:&#8221;CVE-2026-6937&#8243;,&#8221;bulletinFamily&#8221;:&#8221;&#8221;,&#8221;cwe&#8221;:[&#8220;CWE-862&#8243;],&#8221;cvelist&#8221;:null,&#8221;sourceData&#8221;:&#8221;croixhaug 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Booking Calendar \u2014 Simply Schedule Appointments Booking Plugin&#8221;,&#8221;version&#8221;:&#8221;0&#8243;,&#8221;vendor&#8221;:&#8221;croixhaug&#8221;,&#8221;ai_description&#8221;:&#8221;&#8221;,&#8221;ai_severity&#8221;:&#8221;&#8221;,&#8221;ai_vendor&#8221;:&#8221;&#8221;,&#8221;ai_product&#8221;:&#8221;&#8221;,&#8221;ai_version&#8221;:&#8221;&#8221;,&#8221;ai_score&#8221;:0}<\/p>\n","protected":false},"excerpt":{"rendered":"<p>{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;The Appointment Booking Calendar \u2014 Simply Schedule Appointments Booking Plugin plugin for WordPress is vulnerable to Missing Authorization in all versions up to, and 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