CVE-2026-6675
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.
Published:Apr 21, 2026
Last Modified:Apr 22, 2026
EPS:Apr 21, 2026
EPSS Score:0.00048
CVSS Score:5.3
Affected Products
Vendor
Product
Action
Vendor
Cyberchimps
Product
Responsive Blocks – Page Builder For Blocks & Patterns
Cyberchimps
Responsive Blocks – Page Builder For Blocks & Patterns
Vendor
Wordpress
Product
Wordpress
Wordpress
Wordpress
Exploits
No exploit reference
Common Weakness Enumeration
Common Attack Pattern Enumeration and Classification (CAPEC)
References
Common Vulnerability Scoring System
Attack Vector
Network
Adjacent
Local
Physical
Privileges Required
None
Low
High
User Interaction
None
Required
Scope
Unchanged
Changed
Confidentiality
None
Low
High
Integrity
None
Low
High
Availability
None
Low
High
