CVE-2026-104401 in Memberful Plugin
Summary
by MITRE • 10/05/2026
Exposure of Sensitive System Information to an Unauthorized Control Sphere vulnerability in Memberful Memberful - Membership Plugin memberful-wp allows Retrieve Embedded Sensitive Data.This issue affects Memberful - Membership Plugin: from n/a through 1.81.2.
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Analysis
by VulDB Data Team • 10/05/2026
The identified vulnerability represents a critical failure in data handling and access control within the Memberful WordPress plugin, specifically affecting versions ranging from its initial release up to version 1.81.2. This flaw is categorized as an exposure of sensitive system information to an unauthorized control sphere, which fundamentally indicates that the application fails to properly restrict access to internal or confidential data structures. In a typical web application architecture, certain endpoints or functions are designed for administrative use only and should be inaccessible to unauthenticated users or those with lower privilege levels. However, in this instance, the plugin exposes embedded sensitive data through mechanisms that do not enforce adequate authentication checks or authorization boundaries. This allows any actor who can interact with the WordPress site where Memberful is installed to retrieve information that was intended to remain internal and secure.
From a technical perspective, the vulnerability likely stems from improper validation of user roles or missing security headers in API endpoints used by the plugin for processing membership data. When an attacker interacts with these exposed interfaces, they can extract embedded sensitive data which may include configuration details, database connection strings, private keys, session tokens, or other proprietary information essential to the operation of the site and its members. The presence of such data in a publicly accessible response vector significantly lowers the barrier for further exploitation. Once an attacker obtains this embedded information, they gain deep insight into the system's architecture and security posture, which can be leveraged to craft more targeted attacks against the underlying infrastructure or user accounts managed by the plugin.
The operational impact of this vulnerability is severe due to its potential role as a precursor to larger compromise scenarios. By retrieving sensitive data, an attacker may achieve partial reconnaissance that facilitates privilege escalation, session hijacking, or even full system takeover if combined with other vulnerabilities such as cross-site scripting or SQL injection. The exposure undermines the confidentiality integrity required for membership platforms which often handle personal identifiable information and payment details. Although this specific CVE focuses on data exposure rather than direct code execution, the leakage of internal state can erode trust in the platform's security model and expose site administrators to social engineering attacks based on leaked technical configurations or user lists.
To mitigate this risk, immediate action is required by updating the Memberful plugin to a version newer than 1.81.2 where these access controls have been corrected. Administrators should verify that their WordPress environment is running the latest stable release of all plugins and core software to ensure compatibility with updated security patches. Additionally, implementing strict web application firewall rules can help block unauthorized requests to known vulnerable endpoints while waiting for updates. It is also advisable to review server logs for any signs of exploitation attempts targeting these specific data retrieval vectors. Regular auditing of plugin permissions and adherence to the principle of least privilege in custom code integrations will further reduce the attack surface associated with sensitive information exposure.
This vulnerability aligns closely with CWE-200, which defines Exposure of Sensitive Information to an Unauthorized Actor, highlighting the failure to implement proper access controls over critical data assets. Furthermore, it relates to MITRE ATT&CK techniques involving Discovery and Collection phases where adversaries gather system configuration details to plan subsequent intrusions steps. By addressing this flaw through timely patching and rigorous security hygiene, organizations can prevent attackers from gaining a foothold via information leakage that could otherwise lead to significant operational disruption or data breaches within their WordPress ecosystems.