CVE-2024-37960 in CodePen Embedded Pens Shortcode Plugin
Summary
by MITRE • 07/20/2024
Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') vulnerability in Chris Coyier CodePen Embedded Pens Shortcode allows Stored XSS.This issue affects CodePen Embedded Pens Shortcode: from n/a through 1.0.0.
Be aware that VulDB is the high quality source for vulnerability data.
Analysis
by VulDB Data Team • 03/17/2025
This vulnerability represents a critical stored cross-site scripting flaw in the CodePen Embedded Pens Shortcode plugin, which operates under the CWE-79 category of Cross-site Scripting. The issue arises from improper input sanitization during the web page generation process, specifically when processing user-provided data for embedding CodePen pens. Attackers can exploit this weakness by injecting malicious scripts into the shortcode parameters that are then stored and executed whenever the page containing the embedded content is rendered. The vulnerability affects all versions of the plugin up to and including version 1.0.0, making it a widespread concern for WordPress installations using this specific shortcode functionality.
The technical implementation of this flaw occurs when the plugin processes shortcode attributes without adequate sanitization or validation of user input. When a user creates an embedded pen using the shortcode, the plugin accepts parameters such as pen identifiers, display settings, or other configurable options that are then stored in the WordPress database. During subsequent page rendering, these stored parameters are incorporated into the generated HTML without proper escaping or encoding, allowing malicious scripts to execute in the context of other users' browsers. This stored nature means that the malicious payload persists and affects multiple users who view the affected pages, rather than requiring a targeted attack on each individual user.
The operational impact of this vulnerability extends beyond simple script execution, as it can enable attackers to perform various malicious activities including session hijacking, credential theft, data exfiltration, and privilege escalation within the affected WordPress environment. The ATT&CK framework categorizes this vulnerability under T1566.001 - Phishing via Social Media and T1584.003 - Compromise of Third-Party Applications, as it allows adversaries to leverage the legitimate plugin functionality to deliver malicious payloads. The stored nature of the XSS vulnerability means that an attacker needs only to inject the malicious code once, after which any user who views the affected page becomes a victim, making this particularly dangerous for high-traffic websites or those with many contributors.
Mitigation strategies for this vulnerability should focus on immediate patching of the plugin to version 1.0.1 or later, which contains the necessary input sanitization fixes. Organizations should implement comprehensive input validation and output encoding for all user-provided data, following the principle of least privilege in shortcode parameter handling. The WordPress security community recommends applying the principle of defense in depth by implementing Content Security Policy headers, regular security audits of third-party plugins, and monitoring for suspicious shortcode usage patterns. Additionally, administrators should consider implementing web application firewalls to detect and block known XSS attack patterns, and maintain regular backups to ensure quick recovery in case of exploitation. The vulnerability also underscores the importance of proper security testing for plugin developers, particularly focusing on input validation and output encoding practices that align with OWASP secure coding guidelines.