CVE-2023-6959 in Gutenberg Blocks Plugin
Summary
by MITRE • 02/06/2024
The Getwid – Gutenberg Blocks plugin for WordPress is vulnerable to unauthorized modification of data due to a missing capability check on the recaptcha_api_key_manage function in all versions up to, and including, 2.0.3. This makes it possible for authenticated attackers, with subscriber-level access and above, to add, modify, or delete the 'Recaptcha Site Key' and 'Recaptcha Secret Key' settings.
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Analysis
by VulDB Data Team • 04/11/2026
The CVE-2023-6959 vulnerability resides within the Getwid Gutenberg Blocks plugin for WordPress, representing a critical authorization flaw that undermines the security posture of affected systems. This vulnerability specifically targets the recaptcha_api_key_manage function which lacks proper capability verification, creating an exploitable condition that allows authenticated users to manipulate sensitive configuration data. The flaw affects all plugin versions up to and including 2.0.3, indicating a widespread exposure across numerous installations that rely on this popular Gutenberg block plugin for WordPress.
The technical implementation of this vulnerability stems from the absence of capability checks within the plugin's administrative functions, particularly surrounding the reCAPTCHA API key management interface. When an authenticated attacker with subscriber-level privileges or higher accesses the plugin's settings management functionality, they can manipulate the Recaptcha Site Key and Recaptcha Secret Key configuration values without proper authorization. This missing capability check represents a direct violation of the principle of least privilege, where users should only be able to perform actions commensurate with their assigned permissions. The vulnerability operates at the application layer and leverages the existing authentication mechanism to escalate privileges within the plugin's administrative scope.
The operational impact of this vulnerability extends beyond simple data modification, as it provides attackers with the capability to potentially disrupt service availability and compromise security controls. By modifying the reCAPTCHA keys, an attacker could effectively disable the plugin's spam protection mechanisms or replace them with malicious configurations that could be used for credential stuffing attacks or other malicious activities. The vulnerability enables unauthorized modification of critical security parameters, potentially allowing attackers to bypass authentication mechanisms, manipulate user registration processes, or create backdoors for persistent access. This represents a significant risk to WordPress installations that depend on the plugin for form validation and user authentication security measures, as it directly undermines the integrity of the site's security infrastructure.
Mitigation strategies for CVE-2023-6959 should prioritize immediate plugin updates to versions that address the missing capability check vulnerability, as this represents the most direct solution to the identified flaw. Administrators should also implement additional monitoring of plugin configuration changes to detect unauthorized modifications to reCAPTCHA settings, utilizing logging mechanisms and security information and event management systems to track access patterns. The vulnerability aligns with CWE-284, which describes improper access control, and maps to ATT&CK technique T1078.004 for Valid Accounts and T1566.002 for Phishing with Social Engineering, as attackers could leverage this vulnerability to establish persistent access or manipulate authentication flows. Organizations should also consider implementing role-based access controls to limit the privileges of low-privilege users and ensure that only administrators with legitimate need can modify security-critical configuration parameters. Additionally, regular security audits of WordPress plugins and their capabilities should be conducted to identify similar authorization gaps that could potentially be exploited in similar fashion.