CVE-2024-33691 in OptinMonster Plugin
Summary
by MITRE • 04/26/2024
Cross-Site Request Forgery (CSRF) vulnerability in OptinMonster Popup Builder Team OptinMonster.This issue affects OptinMonster: from n/a through 2.15.3.
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Analysis
by VulDB Data Team • 04/03/2025
The CVE-2024-33691 vulnerability represents a critical cross-site request forgery flaw within the OptinMonster Popup Builder plugin, a widely used tool for creating email capture forms and marketing popups on wordpress websites. This vulnerability specifically impacts versions of the OptinMonster plugin ranging from an unspecified initial version through 2.15.3, creating a substantial attack surface for malicious actors targeting wordpress installations. The flaw resides in the plugin's failure to properly validate and authenticate administrative requests, allowing attackers to manipulate the plugin's functionality through crafted requests that appear legitimate to the target system. This type of vulnerability is particularly dangerous because it can be exploited by attackers who have gained access to a victim's browsing session or can trick users into executing unauthorized actions against the vulnerable system.
The technical implementation of this CSRF vulnerability stems from the absence of proper anti-forgery tokens or nonce validation mechanisms within the plugin's administrative interfaces. When administrators perform actions such as creating new popups, modifying existing campaigns, or changing plugin settings, the system should verify that these requests originate from authenticated and authorized sources. However, the OptinMonster plugin fails to implement adequate protection measures, making it possible for attackers to construct malicious requests that can be executed without the administrator's knowledge or consent. This weakness directly violates fundamental security principles outlined in the CWE-352 category, which specifically addresses cross-site request forgery vulnerabilities where applications fail to validate that requests originate from legitimate sources.
The operational impact of this vulnerability extends beyond simple data manipulation or theft, as it can enable attackers to fundamentally alter the behavior of wordpress websites that rely on OptinMonster for their marketing automation. An attacker could potentially create malicious popups that redirect users to phishing sites, modify existing campaigns to collect user data, or even disable legitimate marketing functionality. The vulnerability also presents a significant risk to user privacy and data integrity, as compromised campaigns could be used to harvest personal information from website visitors. This type of attack vector is particularly concerning in the context of the ATT&CK framework's privilege escalation and persistence techniques, as it allows adversaries to establish long-term control over marketing automation systems that may contain sensitive user data or serve as entry points for further attacks.
Mitigation strategies for CVE-2024-33691 should prioritize immediate plugin updates to versions that have addressed the CSRF vulnerability, as this represents the most effective solution for eliminating the immediate threat. System administrators should also implement additional security measures including network segmentation, enhanced monitoring of administrative activities, and regular security audits of wordpress installations. The implementation of additional authentication layers such as two-factor authentication for administrative accounts can provide defense-in-depth protection against unauthorized access attempts. Organizations should also consider implementing web application firewalls to detect and block suspicious request patterns that may indicate CSRF attack attempts. Regular security assessments and vulnerability scanning should be conducted to identify similar weaknesses in other plugins or components of the wordpress ecosystem. The vulnerability underscores the importance of maintaining up-to-date security practices and the necessity of implementing robust input validation and authentication mechanisms across all web applications to prevent unauthorized administrative actions that could compromise system integrity and user data protection.