CVE-2019-14328 in Simple Membership Plugin
Summary
by MITRE
The Simple Membership plugin before 3.8.5 for WordPress has CSRF affecting the Bulk Operation section.
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Analysis
by VulDB Data Team • 09/25/2025
The Simple Membership plugin for WordPress contains a cross-site request forgery vulnerability in its Bulk Operation section that affects versions prior to 3.8.5. This vulnerability allows authenticated attackers with access to a victim's session to perform unauthorized actions within the plugin's administrative interface. The flaw resides in the plugin's handling of bulk operations where proper CSRF protection mechanisms are either absent or insufficiently implemented. Attackers can exploit this weakness by crafting malicious requests that, when executed by an authenticated administrator, perform unintended operations such as user account modifications, role assignments, or other administrative tasks within the membership system.
The technical implementation of this vulnerability stems from the plugin's failure to validate the origin of requests submitted through the bulk operation interface. When administrators navigate to the bulk operations section, the plugin does not enforce proper CSRF tokens or referer validation checks that would normally prevent requests originating from external domains or unauthorized sources. This allows attackers to leverage the administrator's authenticated session to execute malicious bulk operations without their knowledge or consent. The vulnerability specifically impacts the plugin's administrative functionality where multiple users or membership records can be modified simultaneously through batch processing features. According to CWE classification, this represents a weakness in the validation of CSRF tokens, specifically CWE-352, which directly maps to cross-site request forgery vulnerabilities.
The operational impact of this vulnerability extends beyond simple privilege escalation as it can enable attackers to manipulate user access controls, modify membership tiers, or potentially gain unauthorized access to restricted content within the WordPress site. An attacker who successfully exploits this vulnerability could alter user permissions, disable accounts, or create new administrator accounts, thereby compromising the entire membership system and potentially the broader WordPress installation. The risk is particularly elevated when administrators frequently use the bulk operation features, as the attack surface increases with usage frequency. This vulnerability aligns with ATT&CK technique T1078.004 which describes valid accounts used for persistence, as compromised administrators could maintain access through manipulated membership configurations.
Organizations using the Simple Membership plugin should immediately upgrade to version 3.8.5 or later to remediate this vulnerability. The fix typically involves implementing proper CSRF token generation and validation within the bulk operation handlers, ensuring that all requests contain valid authentication tokens that are tied to the user's current session. Additionally, administrators should review their WordPress plugin management practices to ensure timely updates and consider implementing security monitoring for unusual bulk operation activities. The vulnerability demonstrates the critical importance of CSRF protection in administrative interfaces and highlights how seemingly minor implementation gaps can lead to significant security compromises in content management systems. Security teams should also verify that no other plugins within the WordPress ecosystem exhibit similar CSRF vulnerabilities through comprehensive penetration testing and security audits.