CVE-2018-20154 in WP Maintenance Mode Plugin
Summary
by MITRE
The WP Maintenance Mode plugin before 2.0.7 for WordPress allows remote authenticated users to discover all subscriber e-mail addresses.
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Analysis
by VulDB Data Team • 04/21/2020
The vulnerability identified as CVE-2018-20154 affects the WP Maintenance Mode plugin for WordPress, specifically versions prior to 2.0.7. This issue represents a significant information disclosure flaw that undermines the security posture of WordPress installations. The vulnerability exists within the plugin's handling of user data during maintenance mode operations, creating an unintended exposure of sensitive information. Attackers exploiting this weakness can gain unauthorized access to subscriber email addresses, potentially compromising user privacy and enabling further attack vectors.
The technical flaw stems from improper access controls within the plugin's maintenance mode functionality. When administrators configure maintenance mode settings, the plugin fails to adequately restrict access to user email addresses, particularly those of subscribers who have registered on the WordPress site. This weakness allows authenticated users with minimal privileges to access email addresses through specific API endpoints or direct requests to plugin functionality. The vulnerability essentially bypasses the intended access restrictions that should prevent non-administrative users from viewing user contact information during maintenance periods.
The operational impact of this vulnerability extends beyond simple information disclosure, creating potential risks for both site administrators and end users. Subscriber email addresses can be harvested and used for spam campaigns, social engineering attacks, or targeted phishing operations. The exposure of user contact information creates a foundation for more sophisticated attacks including credential stuffing, account takeover attempts, or reputation damage for the website owner. Additionally, this vulnerability undermines user trust in the platform's security measures and could lead to regulatory compliance issues depending on the jurisdiction and data protection requirements.
This vulnerability aligns with CWE-200, which covers "Information Exposure," and represents a specific instance of improper access control that violates security best practices. The issue also maps to ATT&CK technique T1213.002, "Data from Information Repositories," as it involves unauthorized access to user data repositories. Organizations should prioritize updating to WP Maintenance Mode version 2.0.7 or later to address this vulnerability. Security teams should also implement network monitoring to detect unusual access patterns to plugin endpoints and consider restricting access to maintenance mode features to administrative users only. Regular security audits of WordPress plugins and themes remain essential for identifying similar access control weaknesses that could compromise user data privacy.