CVE-2026-6675

MEDIUM

Responsive Blocks <= 2.2.0 - Unauthenticated Open Email Relay via REST API 'email_to' Parameter

Title source: cna
STIX 2.1

Description

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.

References (7)

Core 7
Core References

Scores

CVSS v3 5.3
EPSS 0.0032
EPSS Percentile 24.0%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

CISA SSVC

Vulnrichment
Exploitation none
Automatable yes
Technical Impact partial

Details

CWE
CWE-20
Status published
Products (1)
cyberchimps/Responsive Blocks – Page Builder for Blocks & Patterns < 2.2.0
Published Apr 21, 2026
Tracked Since Apr 21, 2026