CVE-2026-6675: Responsive Blocks <= 2.2.0 - Unauthenticated Open Email Relay via REST API 'email_to' Parameter
The Responsive Blocks – Page Builder for Blocks & Patterns plugin for WordPress is vulnerable to Unauthenticated Open Email Relay in all versions up to, and including, 2.2.0. This is due to insufficient authorization checks and missing server-side validation of the recipient email address supplied via a public REST API route. This makes it possible for unauthenticated attackers to send arbitrary emails to any recipient of their choosing through the affected WordPress site's mail server, effectively turning the site into an open mail relay.
Affected Software
Event History
Frequently Asked Questions
What is the severity of CVE-2026-6675?
CVE-2026-6675 is considered a high severity vulnerability due to its potential for unauthorized email relay.
How do I fix CVE-2026-6675?
To fix CVE-2026-6675, update the Responsive Blocks plugin to version 2.2.1 or later.
Who is affected by CVE-2026-6675?
All users of the Responsive Blocks plugin for WordPress versions up to and including 2.2.0 are affected by CVE-2026-6675.
What type of vulnerability is CVE-2026-6675?
CVE-2026-6675 is an unauthenticated open email relay vulnerability that can be exploited via the REST API.
Is CVE-2026-6675 easy to exploit?
Yes, CVE-2026-6675 can be easily exploited due to insufficient validation of the 'email_to' parameter.