CVE-2024-9873 in Community Plugin
Summary
by MITRE • 10/16/2024
The Community by PeepSo – Social Network, Membership, Registration, User Profiles, Premium – Mobile App plugin for WordPress is vulnerable to Stored Cross-Site Scripting via URLs in posts, comments, and profiles when Markdown support is enabled in all versions up to, and including, 6.4.6.1 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with Subscriber-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.
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Analysis
by VulDB Data Team • 03/05/2025
The vulnerability identified as CVE-2024-9873 affects the Community by PeepSo mobile app plugin for WordPress, specifically targeting versions up to and including 6.4.6.1. This security flaw resides within the plugin's handling of user-generated content when Markdown support is enabled, creating a persistent cross-site scripting vector that can be exploited by authenticated users with subscriber-level privileges or higher. The vulnerability stems from inadequate input sanitization and insufficient output escaping mechanisms within the plugin's content processing pipeline, allowing malicious actors to inject malicious scripts that execute in the context of other users' browsers when they access compromised content.
The technical implementation of this vulnerability occurs when the plugin processes URLs within posts, comments, and user profiles while Markdown support is active. When users with sufficient privileges create or modify content containing malicious script tags within URL parameters or embedded content, the plugin fails to properly sanitize these inputs before storing them in the database. The absence of proper output escaping means that when other users view these stored elements, the malicious scripts execute in their browsers without proper context isolation. This represents a classic stored XSS vulnerability pattern where the malicious payload is permanently stored on the server and executed whenever the affected content is retrieved and rendered.
From an operational perspective, this vulnerability poses significant risks to the security posture of WordPress installations using the affected plugin. Attackers with subscriber-level access can leverage this flaw to execute arbitrary scripts in the browsers of other users, potentially leading to session hijacking, credential theft, or redirection to malicious sites. The impact extends beyond individual user sessions as the vulnerability affects core social networking functionality including posts, comments, and user profiles, making it particularly dangerous in community-driven environments where users frequently interact with content created by others. The vulnerability's persistence means that even after the initial injection, the malicious code continues to execute for any user who accesses the compromised content, creating a continuous threat vector.
The vulnerability aligns with CWE-79, which specifically addresses Cross-Site Scripting flaws in software applications, and demonstrates characteristics consistent with ATT&CK technique T1566.001, which involves social engineering through malicious links or content. Organizations should immediately update to the latest version of the plugin where this vulnerability has been patched, as the affected versions represent a critical security risk. Additionally, administrators should implement proper input validation and output escaping measures at multiple layers, including content sanitization before storage and proper HTML escaping during rendering. Network monitoring should be enhanced to detect suspicious URL patterns within user-generated content, and access controls should be reviewed to ensure users cannot inject malicious content into public-facing areas of the platform. Regular security audits of third-party plugins and immediate patch management protocols are essential to prevent exploitation of similar vulnerabilities in the future.