CVE-2023-1027 in WP Meta SEO Plugin
Summary
by MITRE • 02/28/2023
The WP Meta SEO plugin for WordPress is vulnerable to unauthorized sitemap generation due to a missing capability check on the checkAllCategoryInSitemap function in versions up to, and including, 4.5.3. This makes it possible for authenticated attackers with subscriber-level access to obtain post categories. This vulnerability occurred as a result of the plugin relying on nonce checks as a means of access control, and that nonce being accessible to all authenticated users regardless of role.
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Analysis
by VulDB Data Team • 03/26/2023
The vulnerability identified as CVE-2023-1027 affects the WP Meta SEO plugin for WordPress, representing a critical authorization flaw that undermines the security model of the affected platform. This issue exists within versions up to and including 4.5.3, where the plugin fails to implement proper capability checks for sitemap generation functionality. The specific flaw resides in the checkAllCategoryInSitemap function which lacks adequate access control mechanisms, creating a path for unauthorized information disclosure that directly impacts the confidentiality of post categorization data.
The technical implementation of this vulnerability stems from the plugin's reliance on nonce checks as the sole mechanism for access control rather than implementing proper user role verification. Nonce values in WordPress are typically used to verify the integrity of requests and prevent cross-site request forgery attacks, but they should not serve as the primary authorization mechanism. In this case, the nonce validation is accessible to all authenticated users regardless of their role permissions, effectively allowing attackers with minimal privileges to bypass intended security boundaries. This design flaw aligns with CWE-284, which describes improper access control vulnerabilities where insufficient checks allow unauthorized access to resources.
The operational impact of this vulnerability is significant for WordPress administrators and content creators who rely on the plugin for SEO optimization and sitemap management. An authenticated attacker with subscriber-level access can exploit this weakness to obtain sensitive information about post categories, potentially revealing content structure and organizational patterns that could aid in further exploitation attempts. This information disclosure could enable attackers to map content hierarchies, identify sensitive or unpublished content categories, and potentially plan more sophisticated attacks against the website. The vulnerability essentially creates a backdoor for information gathering that could be leveraged in combination with other attack vectors, making it particularly dangerous in environments where content categorization reveals business or organizational intelligence.
The security implications extend beyond simple information disclosure to encompass potential privilege escalation pathways and reconnaissance opportunities. Attackers could use the leaked category information to craft more targeted phishing attempts, identify content gaps in their target's information architecture, or plan social engineering campaigns that exploit the discovered organizational structure. This vulnerability also demonstrates poor security implementation practices that violate fundamental principles of least privilege and defense in depth, as the plugin fails to properly validate user capabilities before exposing sensitive functionality. Organizations should consider implementing additional monitoring for unusual sitemap access patterns and ensure proper plugin updates are deployed immediately upon patch availability.
Mitigation strategies for this vulnerability should include immediate patching to the latest available version of the WP Meta SEO plugin where the capability check has been properly implemented. Administrators should also review user roles and permissions to ensure that only authorized personnel have access to sensitive plugin features. The implementation of additional monitoring for sitemap generation requests and access patterns can help detect potential exploitation attempts. From a broader security perspective, this vulnerability underscores the importance of proper access control implementation and the dangers of relying solely on nonce validation for authorization purposes. Organizations should conduct comprehensive security reviews of all plugins and themes to identify similar issues, as this represents a common pattern in WordPress plugin development where access control mechanisms are insufficiently implemented or tested. The ATT&CK framework categorizes this type of vulnerability under privilege escalation and reconnaissance techniques, emphasizing how such flaws can enable attackers to gather intelligence and move laterally within compromised systems.