CVE-2024-9520 in UserPlus Plugin
Summary
by MITRE • 10/10/2024
The UserPlus plugin for WordPress is vulnerable to unauthorized access, modification, and loss of data due to a missing capability check on multiple functions in all versions up to, and including, 2.0. This makes it possible for authenticated attackers with subscriber-level permissions or above, to add, modify, or delete user meta and plugin options.
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Analysis
by VulDB Data Team • 05/22/2026
The UserPlus plugin for WordPress presents a critical security vulnerability stemming from insufficient access control mechanisms that permit unauthorized actions by authenticated users. This flaw exists in all versions up to and including 2.0 and specifically affects functions that handle user meta data and plugin configuration options. The vulnerability arises from the absence of proper capability checks that should validate user permissions before executing sensitive operations. Attackers with subscriber-level privileges or higher can exploit this weakness to manipulate core user information and plugin settings, fundamentally compromising the integrity of the WordPress installation.
The technical implementation of this vulnerability manifests through functions that lack proper authorization validation before processing user meta data modifications or plugin option changes. This missing capability check creates a direct path for privilege escalation within the WordPress environment, allowing attackers to perform operations that should be restricted to administrators or users with elevated privileges. The flaw operates at the application layer where WordPress core functions fail to enforce proper access controls, creating an exploitable condition that directly violates standard security principles. According to CWE guidelines, this represents a weakness in authorization mechanisms where proper access control checks are absent or improperly implemented.
The operational impact of this vulnerability extends beyond simple data manipulation to encompass potential system compromise and data integrity breaches. Authenticated attackers can leverage this weakness to modify user profiles, alter user permissions, and manipulate plugin configurations that may affect other system components. The vulnerability enables attackers to potentially establish persistent access points within the WordPress environment, as they can modify user meta data to include malicious configurations or alter existing user accounts to gain broader system access. This weakness can lead to complete system compromise when combined with other vulnerabilities, as attackers can use the modified user data to escalate privileges or create backdoors.
Mitigation strategies for this vulnerability require immediate attention from system administrators and security teams. The most effective approach involves upgrading to the latest version of the UserPlus plugin where the missing capability checks have been implemented. Organizations should also conduct thorough security audits to identify any existing exploitation attempts and review user permissions to minimize the attack surface. Network monitoring should be enhanced to detect anomalous user meta data modifications and plugin option changes that may indicate exploitation attempts. The vulnerability aligns with ATT&CK technique T1078 which covers valid accounts and privilege escalation through unauthorized access to system resources, emphasizing the need for proper access controls and capability validation within WordPress plugins. System administrators should implement principle of least privilege policies and regularly review user roles and capabilities to prevent unauthorized modifications to critical system components.