Threat intelligence

Appointment Booking Calendar <= 1.6.11.8 - Missing Authorization to Unauthenticated Arbitrary Modification via Bulk Appointments REST API Endpoint

CVE-2026-6937 · simply-schedule-appointments

Important: Seeing this vulnerability listed does not mean your website is affected. Exposure depends on whether you run Simply Schedule Appointments at a vulnerable version. How SiteRespond intelligence works

Vulnerability: Appointment Booking Calendar <= 1.6.11.8 - Missing Authorization to Unauthenticated Arbitrary Modification via Bulk Appointments REST API Endpoint
Affected software: simply-schedule-appointments(Plugin)
Affected versions: ≤ 1.6.11.8
Authentication: Unauthenticated
Vulnerability type: Other
CVE: CVE-2026-6937
Published: 27 May 2026
CISA KEV: Not listed in CISA KEV at last catalog refresh
Impact: This advisory describes a other issue in the affected software. Review the source advisory and your installed version to assess exposure.
Source: Data imported from Wordfence Intelligence (advisory ef0f5f9d-788a-4cf8-9747-ada076a69a1f). Methodology and redistribution notes

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