CVE-2026-8608

What is known

The Event Monster – Event Management, Events Calendar, Tickets plugin for WordPress is vulnerable to Insufficient Verification of Data Authenticity in versions up to, and including, 2.1.0. This is due to the capture_payment() AJAX handler (registered via wp_ajax_nopriv_em_capture_payment) trusting client-supplied payment data — including transaction ID, amount, and payment status — without performing any server-side verification against the PayPal API or any other payment gateway, and without nonce or capability checks. This makes it possible for unauthenticated attackers to forge payment records, mark bookings as Completed, and obtain confirmation emails containing valid QR code tickets without making any actual payment.

Business impact

Successful exploitation of CVE-2026-8608, a medium vulnerability (CVSS 5.3) affecting the affected product, may affect the confidentiality, integrity or availability of the vulnerable environment. The exact impact depends on the installed version, exposed interfaces and deployment configuration.

Recommended administrator action

Confirm whether the affected product is present and compare installed versions with the vendor advisory and NVD record. Apply the vendor patch or documented mitigation; until remediation is complete, reduce exposure of affected interfaces, review relevant logs and monitor for indicators of exploitation. DataHouse can support version verification, managed patching, network exposure reduction, log review and backup validation for dedicated, cloud and colocated environments.

Sources

• NVD
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