CVE-2026-66637 in Featured Video Plus Plugin
Summary
by MITRE • 08/18/2026
Contributor Cross Site Scripting (XSS) in Featured Video Plus <= 2.3.3 versions.
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Analysis
by VulDB Data Team • 08/18/2026
The vulnerability identified as Contributor Cross-Site Scripting within the Featured Video Plus plugin, affecting versions up to and including 2.3.3, represents a significant security flaw rooted in insufficient input validation and output encoding mechanisms. This specific weakness allows an attacker with contributor-level or lower privileges on a WordPress installation to inject malicious client-side scripts into web pages viewed by other users. The core of the issue lies in how the plugin handles user-supplied data when managing featured video content, failing to properly sanitize inputs before rendering them within the browser context.
From a technical perspective, this vulnerability is classified under CWE-79, which denotes Improper Neutralization of Input During Web Page Generation commonly known as Cross-Site Scripting. The flaw typically manifests in areas where user input is reflected directly into HTML output without adequate encoding or escaping. In the case of Featured Video Plus, an authenticated attacker can exploit this by manipulating video metadata or associated fields that are stored and subsequently displayed on the frontend or backend interfaces. Because the application does not enforce strict type checking or strip potentially dangerous script tags, event handlers, or JavaScript URIs from these inputs, the browser executes the injected code as if it were legitimate content originating from the trusted domain.
The operational impact of this vulnerability is substantial due to its potential for session hijacking and data theft. By successfully executing arbitrary JavaScript in the context of a victim user's browser, an attacker can bypass same-origin policies that normally restrict web pages from interacting with each other. This capability enables the extraction of sensitive information such as authentication cookies, session tokens, or personal data stored within local storage variables associated with the WordPress admin dashboard. Furthermore, the attack vector facilitates phishing campaigns where the malicious script can dynamically alter page content to mimic legitimate login forms, tricking users into surrendering their credentials. The persistence of this threat is heightened by the fact that it requires only contributor-level access, a role often granted to multiple individuals who may not be fully aware of security implications.
This vulnerability aligns with several tactics within the MITRE ATT&CK framework for enterprise cybersecurity. It primarily falls under the Execution tactic via Browser Rendering, where malicious code runs in the victim's browser environment. Additionally, it relates to Collection through Keylogging or Screen Capture if the injected script captures keystrokes or visual data from the compromised session. The exploitation also touches upon Credential Access as attackers aim to steal cookies and tokens that provide unauthorized access to administrative functions. Understanding these mappings helps security teams prioritize remediation efforts based on broader threat intelligence models rather than isolated incident response metrics.
Mitigation strategies must focus on both immediate patching and long-term defensive coding practices. Administrators should immediately update the Featured Video Plus plugin to a version newer than 2.3.3, where developers have presumably addressed these sanitization gaps. For environments unable to upgrade instantly, implementing Web Application Firewall rules that detect and block common XSS payloads in POST requests targeting video metadata endpoints can provide temporary relief. However, such network-level controls are not substitutes for application-layer fixes. Developers must ensure all user inputs undergo rigorous validation against expected formats and employ context-aware output encoding when rendering data into HTML attributes, JavaScript strings, or plain text bodies. Adhering to OWASP guidelines for input handling will significantly reduce the attack surface associated with similar vulnerabilities in future updates.