CVE-2021-24734 in Compact WP Audio Player Plugin
Summary
by MITRE • 10/18/2021
The Compact WP Audio Player WordPress plugin before 1.9.7 does not escape some of its shortcodes attributes, which could allow users with a role as low as Contributor to perform Stored Cross-Site Scripting attacks.
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Analysis
by VulDB Data Team • 10/22/2021
The Compact WP Audio Player WordPress plugin versions prior to 197 contain a critical stored cross-site scripting vulnerability that affects the core security posture of WordPress installations. This vulnerability stems from insufficient output escaping of shortcode attributes within the plugin's implementation, creating an attack vector that can be exploited by users with minimal privileges. The flaw specifically impacts the plugin's handling of user-supplied data within shortcode parameters, where malicious input is not properly sanitized before being rendered in the web page context.
This vulnerability operates under the Common Weakness Enumeration framework as CWE-79, which categorizes it as a Cross-Site Scripting flaw. The issue manifests when contributors or users with equivalent permissions submit malicious payloads through shortcode attributes that are then stored in the WordPress database. These stored payloads execute when other users view pages containing the affected shortcodes, creating a persistent XSS attack vector. The vulnerability does not require elevated privileges to exploit, making it particularly dangerous as it can be leveraged by attackers who gain access to low-privilege accounts through social engineering or other means.
The operational impact of CVE-2021-24734 extends beyond simple script execution, as it provides attackers with the ability to hijack user sessions, steal sensitive information, and potentially escalate privileges within the WordPress environment. When exploited, the stored XSS can be used to perform actions such as reading cookies, redirecting users to malicious sites, or even executing arbitrary code within the context of the victim's browser. The attack surface is broad since any page utilizing the affected plugin's shortcodes becomes a potential target for exploitation. Security frameworks such as the MITRE ATT&CK matrix classify this vulnerability under the T1566 technique for Phishing and T1059 for Command and Scripting Interpreter, highlighting its potential for credential theft and lateral movement within compromised environments.
Mitigation strategies for this vulnerability require immediate plugin updates to version 197 or later, which contain proper output escaping mechanisms for shortcode attributes. Administrators should also implement additional security measures including regular security audits, monitoring of user activity, and implementing content security policies to limit the impact of potential exploitation. The vulnerability demonstrates the importance of proper input validation and output escaping in web applications, particularly in plugins that handle user-generated content. Organizations should conduct comprehensive vulnerability assessments to identify other plugins with similar issues and establish robust patch management procedures to prevent future occurrences of such security flaws in their WordPress environments.