CVE-2021-4341 in uListing Plugin
Summary
by MITRE • 06/07/2023
The uListing plugin for WordPress is vulnerable to authorization bypass via Ajax due to missing capability checks, missing input validation, and a missing security nonce in the stm_update_email_data AJAX action in versions up to, and including, 1.6.6. This makes it possible for unauthenticated attackers to change any WordPress option in the database.
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Analysis
by VulDB Data Team • 04/09/2026
The uListing plugin for WordPress presents a critical authorization bypass vulnerability through its Ajax endpoint implementation that fundamentally undermines the security model of the WordPress platform. This vulnerability exists within the stm_update_email_data AJAX action and affects all versions up to and including 1.6.6, creating a pathway for unauthenticated attackers to manipulate core WordPress configurations without proper authentication. The flaw stems from the absence of proper capability checks that should verify user permissions before executing sensitive operations, allowing malicious actors to exploit this gap in the access control mechanism.
The technical implementation of this vulnerability demonstrates multiple layers of security failure that compound the risk. The missing capability checks represent a fundamental breakdown in the principle of least privilege, where the system fails to validate whether the requesting user possesses adequate permissions to modify WordPress options. Additionally, the absence of input validation creates opportunities for data injection attacks that could be leveraged to manipulate database entries. The missing security nonce further weakens the authentication mechanism, as nonces are specifically designed to prevent cross-site request forgery attacks by ensuring that requests originate from legitimate sources within the WordPress environment.
The operational impact of this vulnerability extends far beyond simple unauthorized access, as it allows attackers to modify any WordPress option in the database. This broad scope of potential manipulation includes critical configuration parameters that control user roles, plugin settings, theme options, and core WordPress behaviors. Attackers could potentially disable security plugins, modify user permissions, alter site settings to redirect traffic, or even establish persistent backdoors through configuration changes. The implications for WordPress sites using affected versions are severe, as this vulnerability essentially provides attackers with administrative capabilities without requiring valid credentials.
Mitigation strategies for this vulnerability should focus on immediate remediation through plugin updates to versions that address the authorization bypass issues. Organizations should implement comprehensive monitoring of their WordPress installations to detect unauthorized configuration changes and establish automated patch management processes to prevent such vulnerabilities from remaining unaddressed. The vulnerability aligns with CWE-863, which addresses "Incorrect Authorization," and maps to ATT&CK technique T1078.004 for Valid Accounts, as attackers can exploit this weakness to gain elevated privileges without proper authentication. Security teams should also consider implementing web application firewalls that can detect and block suspicious Ajax requests targeting known vulnerable endpoints, while maintaining detailed audit logs of all configuration changes to enable rapid incident response and forensic analysis.