CVE-2026-83532 in Custom Menu Wizard Widget Plugin
Summary
by MITRE • 09/12/2026
The Custom Menu Wizard Widget WordPress plugin through 3.3.1 does not sanitize and escape several shortcode attributes before rendering them into HTML, allowing users with contributor-level access and above to inject arbitrary web scripts that execute when the affected content is viewed.
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Analysis
by VulDB Data Team • 09/12/2026
The vulnerability identified in the Custom Menu Wizard Widget for WordPress versions up to 3.3.1 represents a classic Cross-Site Scripting (XSS) flaw rooted in insufficient input validation and output encoding mechanisms. The core technical issue lies within the plugin's handling of shortcode attributes, which are processed without adequate sanitization or escaping before being rendered into HTML content. This architectural oversight allows malicious actors to inject arbitrary JavaScript code directly into the page structure when specific widget configurations are saved via the WordPress administration interface. Because the vulnerability affects how data is written back to the database and subsequently displayed on the frontend, it creates a persistent storage vector for attacks that can compromise user sessions or deface websites if not properly mitigated by theme developers or security plugins.
From an operational perspective, this flaw specifically impacts users with contributor-level access and above within the WordPress ecosystem. While lower-privileged roles such as subscribers typically cannot modify widget settings, contributors possess sufficient permissions to edit post content and potentially interact with certain plugin interfaces depending on specific configuration states. An attacker leveraging this vulnerability can execute arbitrary scripts in the context of any user who views the affected page or admin panel section where the malicious shortcode is rendered. This execution environment allows for session hijacking through cookie theft, credential harvesting via keyloggers embedded in the injected script, or redirection to phishing sites designed to steal administrative credentials. The persistence of this attack vector means that even after the initial injection, every subsequent view of the compromised content triggers the malicious payload, amplifying the potential blast radius across multiple user sessions and browsers.
This vulnerability aligns with Common Weakness Enumeration (CWE) identifiers such as CWE-79, which classifies Improper Neutralization of Input During Web Page Generation commonly known as Cross-site Scripting. Furthermore, within the MITRE ATT&CK framework for enterprise security, this behavior maps to techniques involving Stored XSS under the Tactic Execution phase, specifically leveraging client-side code injection to maintain persistence or perform lateral movement once initial access is gained through compromised contributor accounts. The lack of context-aware escaping means that special characters are not converted into their safe HTML entity equivalents, allowing browser interpreters to parse injected tags as executable commands rather than static text data.
To mitigate this risk, immediate action should be taken by updating the Custom Menu Wizard Widget plugin to a version greater than 3.3.1 where these sanitization routines have been corrected. For organizations unable to update immediately due to compatibility constraints with other plugins or custom themes, implementing Web Application Firewall rules can provide temporary protection by filtering out malicious script tags and event handlers in HTTP requests targeting the WordPress admin area. Additionally, enforcing strict Content Security Policy headers on the web server can significantly reduce the impact of successful XSS attempts by restricting the sources from which scripts are allowed to load and execute. Regular auditing of plugin code for proper use of WordPress sanitization functions like wp_kses_post or esc_attr is also recommended to prevent similar vulnerabilities in other custom developments or third-party extensions that handle user-supplied input destined for HTML output.