CVE-2021-4366 in PWA for WP Plugin
Summary
by MITRE • 06/07/2023
The PWA for WP & AMP plugin for WordPress is vulnerable to authorization bypass due to a missing capability check on the pwaforwp_update_features_options function in versions up to, and including, 1.7.32. This makes it possible for authenticated attackers to change the otherwise restricted settings within the plugin.
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Analysis
by VulDB Data Team • 07/05/2023
The vulnerability identified as CVE-2021-4366 affects the PWA for WP & AMP plugin for WordPress, specifically targeting versions up to and including 1.7.32. This represents a critical authorization bypass flaw that undermines the plugin's security model and exposes sensitive configuration options to unauthorized modification by authenticated users who should not possess such privileges. The vulnerability stems from a fundamental missing capability check within the plugin's codebase, creating a pathway for privilege escalation that directly violates core security principles of least privilege and access control.
The technical flaw manifests in the pwaforwp_update_features_options function which fails to properly validate user permissions before allowing modification of restricted plugin settings. This function serves as a critical entry point for administrative configuration changes within the plugin's framework, yet lacks proper authorization verification mechanisms. Attackers who have gained authentication access to the WordPress system can exploit this weakness to modify features and settings that should only be accessible to administrators or users with elevated privileges. The vulnerability operates at the application layer and directly impacts the plugin's ability to enforce proper access controls, making it particularly dangerous in multi-user environments where different permission levels exist.
The operational impact of this vulnerability extends beyond simple configuration changes, as it allows attackers to potentially compromise the entire plugin functionality and underlying WordPress security posture. An authenticated attacker could modify core Progressive Web App settings, disable security features, or alter plugin behavior in ways that could degrade service availability or create additional attack vectors. This authorization bypass can lead to more severe consequences when combined with other vulnerabilities, as it provides a foothold for further exploitation within the WordPress environment. The vulnerability affects all users who have authenticated access to the WordPress administration area, making it particularly concerning for sites with multiple user roles and varying permission levels.
Mitigation strategies should focus on immediate plugin updates to versions that address the missing capability check, as well as implementing additional security measures such as role-based access reviews and monitoring for unauthorized configuration changes. Administrators should conduct comprehensive access control audits to identify any potential exploitation that may have already occurred. The vulnerability aligns with CWE-284 which describes improper access control mechanisms, and represents a clear violation of the principle of least privilege. From an ATT&CK framework perspective, this vulnerability maps to privilege escalation techniques and could enable further lateral movement within the WordPress environment, particularly when combined with other reconnaissance and exploitation activities that target the broader WordPress ecosystem. Organizations should also consider implementing web application firewalls and monitoring solutions to detect anomalous configuration changes that may indicate exploitation attempts.