CVE-2024-0893 in Schema App Structured Data Plugin
Summary
by MITRE • 05/24/2024
The Schema App Structured Data plugin for WordPress is vulnerable to unauthorized modification of data due to a missing capability check on the MarkupUpdate function in all versions up to, and including, 2.1.0. This makes it possible for authenticated attackers, with subscriber access or higher, to update or delete post metadata.
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Analysis
by VulDB Data Team • 04/05/2025
The vulnerability identified as CVE-2024-0893 affects the Schema App Structured Data plugin for WordPress, representing a critical authorization flaw that undermines the integrity of post metadata management. This issue stems from a fundamental missing capability check within the MarkupUpdate function, which is present in all plugin versions up to and including 2.1.0. The flaw allows authenticated attackers who possess subscriber-level privileges or higher to manipulate or delete post metadata without proper authorization, creating a significant vector for data integrity compromise.
The technical implementation of this vulnerability resides in the plugin's insufficient access control mechanisms within the MarkupUpdate function. When an authenticated user invokes this function, the system fails to validate whether the user possesses the appropriate permissions to modify post metadata. This missing capability check violates core security principles and creates an unauthorized modification pathway that bypasses WordPress's standard permission model. The vulnerability specifically targets post metadata operations, which can include structured data markup configurations, schema.org tags, and other semantic web elements that enhance content discoverability and search engine optimization.
From an operational perspective, this vulnerability presents a substantial risk to content management systems utilizing the affected plugin. Attackers with subscriber-level access can exploit this flaw to corrupt or manipulate structured data markup, potentially leading to search engine ranking penalties, content misrepresentation, or even more severe data integrity issues. The impact extends beyond simple metadata modification as compromised structured data can affect how content appears in search results, potentially leading to user confusion or loss of traffic. Additionally, the vulnerability can be leveraged to create persistent backdoors or to establish more sophisticated attack vectors by manipulating content metadata that may be used in automated content processing systems.
The security implications of CVE-2024-0893 align with CWE-284, which addresses improper access control issues in software systems. This classification emphasizes the fundamental flaw in privilege management where the system fails to properly verify user permissions before executing sensitive operations. The vulnerability also maps to ATT&CK technique T1078 which covers valid accounts, as it allows attackers with minimal privileges to escalate their effective access within the system. Organizations running WordPress sites with the affected plugin should prioritize immediate remediation through version updates, as the vulnerability affects all versions up to 2.1.0 and represents a persistent risk to data integrity.
Mitigation strategies should include immediate patching of the Schema App Structured Data plugin to version 2.1.1 or later, where the capability check has been implemented. System administrators should also conduct thorough audits of post metadata across affected sites to identify any unauthorized modifications that may have occurred. Additional protective measures include implementing strict role-based access controls, monitoring user activities for suspicious metadata modifications, and ensuring that only trusted administrators have access to content management functions. The vulnerability underscores the importance of proper capability validation in web applications and serves as a reminder that even seemingly minor access control oversights can create significant security risks in content management systems.