CVE-2019-25151 in Funnel Builder Plugin
Summary
by MITRE • 06/07/2023
The Funnel Builder plugin for WordPress is vulnerable to authorization bypass due to a missing capability check on the activate_plugin function in versions up to, and including, 1.3.0. This makes it possible for authenticated attackers to activate any plugin on the vulnerable service.
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Analysis
by VulDB Data Team • 07/05/2023
The vulnerability identified as CVE-2019-25151 affects the Funnel Builder plugin for WordPress, specifically versions up to and including 1.3.0. This represents a critical authorization bypass flaw that undermines the fundamental security model of the WordPress platform. The issue stems from a missing capability check within the activate_plugin function, which is a core administrative operation that should only be executable by users with appropriate privileges. The absence of proper access controls creates a pathway for malicious actors who have gained authentication access to the WordPress system to escalate their privileges and activate arbitrary plugins without proper authorization. This vulnerability directly violates the principle of least privilege and demonstrates a critical failure in the plugin's security implementation.
From a technical perspective, the flaw occurs within the plugin's administrative interface where the activate_plugin function fails to verify whether the requesting user possesses the necessary capabilities to perform plugin activation. This missing capability check creates an arbitrary code execution vector through plugin activation, as attackers can leverage this vulnerability to install malicious plugins that could contain backdoors, malware, or other harmful code. The vulnerability is particularly dangerous because it allows authenticated attackers to perform actions that should be restricted to administrators or users with specific privileges. According to CWE classification, this represents a weakness in the authorization mechanism, specifically CWE-285: Improper Authorization, which is categorized under the broader category of access control vulnerabilities. The issue aligns with ATT&CK technique T1059.001: Command and Scripting Interpreter - PowerShell, as attackers can use this vulnerability to establish persistent access through plugin installation.
The operational impact of this vulnerability extends beyond simple privilege escalation, as it enables attackers to fundamentally alter the security posture of the affected WordPress installation. Once an attacker activates a malicious plugin, they can establish persistent access, exfiltrate data, or use the compromised system as a staging ground for further attacks. The vulnerability affects any authenticated user who can access the WordPress admin interface, which could include contributors, editors, or even subscribers depending on the specific site configuration. This makes the attack surface significantly larger than initially apparent, as attackers do not need to perform complex exploitation techniques to gain elevated privileges. The potential for data breach, system compromise, and further lateral movement within the network makes this vulnerability particularly concerning for organizations relying on WordPress platforms.
Mitigation strategies for CVE-2019-25151 must address both immediate remediation and long-term security improvements. The primary and most effective mitigation is upgrading the Funnel Builder plugin to version 1.3.1 or later, which contains the necessary capability checks to prevent unauthorized plugin activation. Organizations should also implement proper access control measures, including role-based access control and regular privilege reviews to ensure that users only possess the minimum necessary permissions. Network segmentation and monitoring should be enhanced to detect suspicious plugin activation activities, particularly when new plugins are installed or activated without proper authorization. Security hardening practices such as disabling unnecessary administrative functions, implementing multi-factor authentication, and conducting regular security audits of installed plugins should be enforced. Additionally, organizations should maintain up-to-date vulnerability management processes that include automated scanning for known vulnerabilities in WordPress plugins and themes, as well as regular security assessments to identify and remediate similar authorization bypass issues across their digital infrastructure.