CVE-2026-6675 (GCVE-0-2026-6675)

Vulnerability from cvelistv5 – Published: 2026-04-21 02:25 – Updated: 2026-04-21 13:22
VLAI?
Title
Responsive Blocks <= 2.2.0 - Unauthenticated Open Email Relay via REST API 'email_to' Parameter
Summary
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.
Severity ?
5.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
CWE
  • CWE-20 - Improper Input Validation
Assigner
References
Impacted products
Vendor Product Version
cyberchimps Responsive Blocks – Page Builder for Blocks & Patterns Affected: 0 , ≤ 2.2.0 (semver)
Create a notification for this product.
Credits
Even Stokkedalen
Show details on NVD website
To clipboard 

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Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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