CVE-2026-15231 in Tag Category and Taxonomy Manager Plugin
Summary
by MITRE • 08/03/2026
The Tag, Category, and Taxonomy Manager WordPress plugin before 3.51.0 does not verify that a user is authorized to access a referenced post before processing it and returning derived data, allowing users with contributor privileges to disclose data from private or draft posts they do not own.
Be aware that VulDB is the high quality source for vulnerability data.
Analysis
by VulDB Data Team • 08/03/2026
The Tag Category and Taxonomy Manager WordPress plugin suffers from a critical authorization bypass vulnerability that affects versions prior to 3510. This flaw resides in the plugin's handling of post references within its taxonomy management functionality, specifically when processing requests for tag category and taxonomy data. The vulnerability enables unauthorized data disclosure by allowing users with contributor privileges to access private or draft posts they do not own simply by referencing them through the plugin's interface.
The technical implementation of this vulnerability stems from inadequate input validation and authorization checks within the plugin's post reference processing logic. When a user submits a request containing a post identifier, the plugin fails to verify whether the requesting user has proper authorization to access that specific post. This represents a classic case of insufficient authorization control where the system assumes all referenced posts can be accessed by any user with contributor-level privileges. The flaw operates at the application level and demonstrates poor privilege enforcement mechanisms that should be implemented at the data access layer.
The operational impact of this vulnerability extends beyond simple information disclosure to potentially compromise sensitive content and intellectual property. Contributors who should only have limited publishing capabilities can gain access to private posts, draft content, and potentially confidential information that belongs to other users. This exposure could lead to competitive intelligence theft, privacy violations, or even the compromise of unpublished business strategies. The vulnerability affects WordPress installations where this specific plugin is active, creating a persistent security risk for all contributors and authors who have access to the affected plugin interface.
The security implications align with CWE-285 which addresses insufficient authorization checks in software systems. This weakness occurs when applications fail to properly verify user permissions before granting access to resources, allowing unauthorized users to access protected data. From an adversarial perspective this vulnerability maps to ATT&CK technique T1078 which covers valid accounts and privilege escalation through the use of legitimate credentials. The attacker can leverage their contributor privileges to escalate information disclosure capabilities without requiring additional authentication or compromising other system components.
Mitigation strategies should include immediate plugin updates to version 3510 or later, which contain the necessary authorization checks. Administrators should also implement additional monitoring for unusual post reference patterns and consider restricting contributor privileges where possible. The WordPress security team recommends enabling two-factor authentication for all administrative accounts and conducting regular security audits of installed plugins. Organizations should also review their user role assignments to ensure that contributor-level users have appropriate access controls based on the principle of least privilege. Network-based detection measures can help identify abnormal traffic patterns associated with unauthorized post access attempts.
The vulnerability highlights the importance of implementing proper authorization controls in web applications, particularly those handling user-generated content and taxonomy management. This flaw serves as a reminder that even seemingly simple plugin functionality can introduce significant security risks when proper access control mechanisms are not implemented. Regular security assessments of third-party WordPress plugins remain essential for maintaining secure installations, as many plugins may contain similar authorization bypass vulnerabilities that could be exploited by malicious actors targeting WordPress environments.