CVE-2021-24943: The Registrations for the Events Calendar WordPress plugin before 2.7.6 does not sanitise and escape the event_id in the rtec_send_unregister_link AJAX action…

PriorityP180critical9.8CVSS 3.1

AVNACLPRNUINSUCHIHAH

ITWEXPLOITVulnCheck KEV

Exploited in the wild

EPSS

7.47%

93.7th percentile

The Registrations for the Events Calendar WordPress plugin before 2.7.6 does not sanitise and escape the event_id in the rtec_send_unregister_link AJAX action (available to both unauthenticated and authenticated users) before using it in a SQL statement, leading to an unauthenticated SQL injection.

Affected

1 ranges

Vendor	Product	Version range	Fixed in
roundupwp	registrations_for_the_events_calendar	< 2.7.6	2.7.6

Detection & IOCsextracted from sources · hover to see the quote

otherrtec_send_unregister_link↗

otherRegistrations for the Events Calendar < 2.7.6

→Monitor HTTP requests to WordPress AJAX endpoint (wp-admin/admin-ajax.php) with action=rtec_send_unregister_link and a manipulated/SQLi-payload event_id parameter; the action is accessible to unauthenticated users. ↗
→A successful exploitation response returns HTTP 200 and contains the string 'Please enter the email you registered with' in the body — use this as a confirmation indicator in WAF/proxy logs.

·The Nuclei/probe template digest provided can be used to verify template integrity; ensure the template version targets plugin versions below 2.7.6 only.
·The SQL injection is exploitable by unauthenticated users, so authentication-based detection filters will miss attacks; ensure unauthenticated AJAX traffic is also inspected. ↗

CVSS provenance

nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

nvdv2.07.5HIGHAV:N/AC:L/Au:N/C:P/I:P/A:P

vulncheck9.8CRITICAL

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