CVE-2023-39311 in Fusion Builder Plugin
Summary
by MITRE • 03/27/2024
Cross-Site Request Forgery (CSRF) vulnerability in ThemeFusion Fusion Builder.This issue affects Fusion Builder: from n/a through 3.11.1.
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Analysis
by VulDB Data Team • 04/12/2025
The Cross-Site Request Forgery vulnerability identified as CVE-2023-39311 resides within the ThemeFusion Fusion Builder plugin, a widely used page builder component for wordpress platforms. This vulnerability represents a critical security flaw that allows attackers to execute unauthorized actions on behalf of authenticated users within the affected system. The vulnerability specifically impacts versions of Fusion Builder ranging from an unspecified starting point through version 3.11.1, indicating that all versions within this range are potentially susceptible to exploitation. The issue stems from inadequate validation of cross-site requests, which undermines the fundamental security mechanisms designed to prevent unauthorized modifications to user accounts or system configurations. This flaw directly violates the principles of web application security by enabling malicious actors to manipulate user sessions and perform actions without proper authorization. The vulnerability falls under the Common Weakness Enumeration category CWE-352, which specifically addresses Cross-Site Request Forgery weaknesses in web applications. From an operational perspective, this vulnerability poses significant risks to wordpress installations that utilize the Fusion Builder plugin, as it could allow attackers to modify content, alter user permissions, or perform administrative actions that compromise the entire website's integrity and security posture. The attack vector typically involves tricking authenticated users into clicking malicious links or visiting compromised websites that submit requests to the vulnerable Fusion Builder endpoints. The impact extends beyond simple data modification, as successful exploitation could lead to complete system compromise, data exfiltration, or the establishment of persistent backdoors within the affected wordpress environment.
The technical implementation of this CSRF vulnerability demonstrates a failure in proper request validation mechanisms within the Fusion Builder plugin's architecture. Attackers can craft malicious requests that appear legitimate to the server because they lack proper anti-CSRF token validation or session management controls. This weakness enables attackers to leverage the authenticated user's session to perform unauthorized operations against the Fusion Builder interface, potentially allowing them to modify page layouts, insert malicious code, or alter plugin configurations. The vulnerability's presence in versions through 3.11.1 suggests that the developers failed to implement adequate security controls during the development lifecycle, particularly in the handling of user requests and session validation processes. The ATT&CK framework categorizes this vulnerability under the T1566 technique for Initial Access through Social Engineering, as attackers can exploit this weakness through phishing campaigns or compromised websites. Security professionals should note that this vulnerability represents a significant risk to wordpress ecosystems, as Fusion Builder is commonly used across various wordpress installations, making the potential attack surface substantial. The lack of proper CSRF protection mechanisms within the plugin's request handling pipeline creates an exploitable entry point that bypasses standard authentication checks and authorization controls.
Organizations utilizing the Fusion Builder plugin must implement immediate remediation measures to address this CSRF vulnerability. The most effective mitigation strategy involves updating to the latest available version of the plugin where the vulnerability has been patched and properly addressed. Security teams should also consider implementing additional protective measures such as network-level controls, web application firewalls, and monitoring solutions that can detect and prevent unauthorized requests to the affected endpoints. The implementation of anti-CSRF tokens within all user-facing forms and API endpoints should be mandatory across all wordpress installations using this plugin. Regular security audits and penetration testing should be conducted to identify similar vulnerabilities within the wordpress ecosystem and other third-party plugins. Additionally, administrators should review and implement proper access controls, ensure that users have appropriate privilege levels, and maintain comprehensive logging of all administrative activities. The vulnerability serves as a reminder of the critical importance of maintaining up-to-date software components and implementing proper security controls throughout the application development lifecycle. Organizations should also consider implementing security awareness training for administrators to recognize potential social engineering attacks that could exploit this vulnerability. The remediation process should include thorough testing of updated versions to ensure that security patches do not introduce regressions or compatibility issues within existing wordpress installations.