Threat intelligence

Booking calendar, Appointment Booking System <= 3.2.36 - Missing Authorization to Unauthenticated Arbitrary Modification via wpdevart_payment AJAX Action

CVE-2026-8840 · booking-calendar

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

Vulnerability: Booking calendar, Appointment Booking System <= 3.2.36 - Missing Authorization to Unauthenticated Arbitrary Modification via wpdevart_payment AJAX Action
Affected software: booking-calendar(Plugin)
Affected versions: ≤ 3.2.36
Authentication: Unauthenticated
Vulnerability type: Other
CVE: CVE-2026-8840
Published: 14 August 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 88409bb0-5cb0-4f63-b8f0-d72f54fa17b0). Methodology and redistribution notes

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