CVE-2026-6675 | cyberchimps Responsive Blocks Plugin up to 2.2.0 on WordPress Public REST API Route input validation

VDB-358401 · CVE-2026-6675 · GCVE-0-2026-6675 CYBERCHIMPS RESPONSIVE BLOCKS PLUGIN UP TO 2.2.0 ON WORDPRESS PUBLIC REST API ROUTE INPUT VALIDATION HISTORYDIFFRELATEJSONXMLCTI CVSS Meta Temp Score Current Exploit Price (≈) CTI Interest Score 6.2 $0-$5k 2.25+ Summaryinfo A vulnerability, which was classified as critical, has been found in cyberchimps Responsive Blocks Plugin up to 2.2.0 on WordPress. Affected is an unknown function of the component Public REST API Route. Performing a manipulation results in input validation. This vulnerability is identified as CVE-2026-6675. The attack can be initiated remotely. There is not any exploit available. It is advisable to upgrade the affected component. Detailsinfo A vulnerability, which was classified as critical, was found in cyberchimps Responsive Blocks Plugin up to 2.2.0 on WordPress. This affects an unknown functionality of the component Public REST API Route. The manipulation with an unknown input leads to a input validation vulnerability. CWE is classifying the issue as CWE-20. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is: 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. The weakness was released by Even Stokkedalen. The advisory is shared at wordfence.com. This vulnerability is uniquely identified as CVE-2026-6675 since 04/20/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Neither technical details nor an exploit are publicly available. Upgrading to version 2.1.9 eliminates this vulnerability. Productinfo Type WordPress Plugin Vendor cyberchimps Name Responsive Blocks Plugin Version 2.0 2.1 2.2.0 CPE 2.3info 🔒 🔒 🔒 CPE 2.2info 🔒 🔒 🔒 CVSSv4info VulDB Vector: 🔒 VulDB Reliability: 🔍 CVSSv3info VulDB Meta Base Score: 6.3 VulDB Meta Temp Score: 6.2 VulDB Base Score: 7.3 VulDB Temp Score: 7.0 VulDB Vector: 🔒 VulDB Reliability: 🔍 CNA Base Score: 5.3 CNA Vector (Wordfence): 🔒 CVSSv2info Vector Complexity Authentication Confidentiality Integrity Availability Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock VulDB Base Score: 🔒 VulDB Temp Score: 🔒 VulDB Reliability: 🔍 Exploitinginfo Class: Input validation CWE: CWE-20 CAPEC: 🔒 ATT&CK: 🔒 Physical: No Local: No Remote: Yes Availability: 🔒 Status: Not defined Price Prediction: 🔍 Current Price Estimation: 🔒 0-Day Unlock Unlock Unlock Unlock Today Unlock Unlock Unlock Unlock Threat Intelligenceinfo Interest: 🔍 Active Actors: 🔍 Active APT Groups: 🔍 Countermeasuresinfo Recommended: Upgrade Status: 🔍 0-Day Time: 🔒 Upgrade: Responsive Blocks Plugin 2.1.9 Timelineinfo 04/20/2026 CVE reserved 04/21/2026 +1 days Advisory disclosed 04/21/2026 +0 days VulDB entry created 04/21/2026 +0 days VulDB entry last update Sourcesinfo Advisory: wordfence.com Researcher: Even Stokkedalen Status: Confirmed CVE: CVE-2026-6675 (🔒) GCVE (CVE): GCVE-0-2026-6675 GCVE (VulDB): GCVE-100-358401 Entryinfo Created: 04/21/2026 07:16 Changes: 04/21/2026 07:16 (66) Complete: 🔍 Cache ID: 99:6D6:101 Discussion No comments yet. Languages: en. Please log in to comment. ◂ PreviousOverviewNext ▸