CVE-2026-57650 in Magazine Blocks Plugin
Summary
by MITRE • 06/26/2026
Contributor Cross Site Scripting (XSS) in Magazine Blocks <= 1.8.3 versions.
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Analysis
by VulDB Data Team • 06/26/2026
The vulnerability under consideration involves a contributor cross site scripting flaw within the Magazine Blocks plugin for WordPress, affecting versions up to and including 1.8.3. This represents a critical security weakness that allows unauthorized users with contributor level privileges to execute malicious scripts within the context of other users' browsers. The issue stems from insufficient input validation and output escaping mechanisms within the plugin's codebase, specifically when processing user-generated content submitted through the contributor role interface.
The technical implementation of this vulnerability occurs due to improper sanitization of data entered by contributors who can submit posts, comments, or other content through the WordPress admin panel. When the Magazine Blocks plugin processes this data without adequate filtering or encoding, it fails to prevent malicious script execution within the browser context of authenticated users. This flaw directly aligns with CWE-79 which defines cross site scripting as a weakness where software does not properly encode output or validate input, allowing attackers to inject client-side scripts into web applications.
From an operational perspective, this vulnerability creates significant risk for WordPress sites utilizing Magazine Blocks plugin since contributors typically have access to publish content and can manipulate various post elements. Attackers with contributor accounts can craft malicious payloads that execute when other users view the affected content, potentially leading to session hijacking, data theft, or redirection to malicious sites. The impact extends beyond simple script execution as it can serve as a stepping stone for more sophisticated attacks such as privilege escalation or persistent backdoor establishment within the compromised WordPress environment.
The attack vector relies on the principle that contributors have sufficient permissions to create and publish content but lack proper security controls to prevent malicious submissions. This vulnerability demonstrates poor adherence to the principle of least privilege and inadequate input sanitization practices that are fundamental requirements in secure web application development. According to ATT&CK framework category T1548.003, this represents a technique for Privilege Escalation through the exploitation of web application vulnerabilities.
Mitigation strategies include immediate patching to version 1.8.4 or later which addresses the input validation issues, implementing additional security layers such as content security policies that restrict script execution, and conducting thorough code reviews for all user-submitted content processing functions. Organizations should also consider role-based access controls that limit contributor capabilities to prevent potential exploitation of such vulnerabilities, while monitoring for any suspicious activities related to content creation or modification within the affected plugin. Regular security auditing of third-party plugins remains essential to identify similar weaknesses in the WordPress ecosystem.
The vulnerability highlights the critical importance of input validation and output escaping mechanisms in web applications, particularly those handling user-generated content through administrative interfaces. It serves as a reminder that even seemingly limited user roles can pose significant security risks when proper sanitization controls are absent from application code. The remediation process should include not only updating the vulnerable plugin but also implementing comprehensive security measures to prevent similar issues across other components of the WordPress installation.