CVE-2024-6688 in Oxygen Builder Plugin
Summary
by MITRE • 08/27/2024
The Oxygen Builder plugin for WordPress is vulnerable to unauthorized modification of data due to a missing capability check on the oxy_save_css_from_admin AJAX action in all versions up to, and including, 4.8.3. This makes it possible for authenticated attackers, with Subscriber-level access and above, to update stylesheets.
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Analysis
by VulDB Data Team • 08/28/2024
The vulnerability identified as CVE-2024-6688 affects the Oxygen Builder plugin for WordPress, representing a critical authorization flaw that undermines the security posture of affected websites. This issue resides within the plugin's AJAX handling mechanism, specifically targeting the oxy_save_css_from_admin endpoint that manages stylesheet modifications. The vulnerability exists in all versions up to and including 4.8.3, indicating a widespread exposure across the plugin's user base. The flaw stems from an insufficient capability verification process that fails to properly validate user permissions before allowing stylesheet modifications, creating a pathway for unauthorized data manipulation.
The technical implementation of this vulnerability demonstrates a classic missing authorization check pattern that aligns with CWE-863, or "Incorrect Authorization," where the system fails to verify that the requesting user possesses the necessary privileges to perform the requested operation. The oxygen builder plugin's AJAX action lacks proper capability verification, allowing any authenticated user with Subscriber-level access or higher to execute stylesheet modifications through the admin interface. This represents a privilege escalation vulnerability where users with minimal permissions can manipulate core styling elements of the website, potentially leading to broader security implications including potential cross-site scripting attacks through malicious CSS injection.
From an operational standpoint, this vulnerability creates significant risks for WordPress websites utilizing the Oxygen Builder plugin. An attacker with Subscriber-level access can modify CSS files to inject malicious code, alter website appearance to facilitate social engineering attacks, or create persistent backdoors through compromised styling elements. The impact extends beyond simple visual modifications as CSS files often contain references to external resources and can be leveraged to load malicious content or redirect users to phishing sites. This vulnerability particularly affects websites where multiple users have access to subscriber accounts or where user registration is open, as these scenarios increase the likelihood of exploitation.
The security implications of CVE-2024-6688 align with ATT&CK technique T1078.004, "Valid Accounts: Cloud Accounts," as authenticated users can leverage their existing credentials to perform unauthorized modifications. Additionally, this vulnerability supports ATT&CK technique T1566.001, "Phishing: Spearphishing Attachment," through potential CSS-based phishing vectors that could be implemented through the compromised styling capabilities. Organizations should implement immediate mitigations including plugin updates to version 4.8.4 or later, which addresses this capability check deficiency. System administrators should also consider implementing additional access controls, monitoring for unusual CSS modification patterns, and conducting security audits of user accounts to identify potential compromised credentials. The vulnerability underscores the importance of proper input validation and capability checks in AJAX endpoints, as outlined in the OWASP Top Ten 2021 category A04:2021 - "Insecure Design" and specifically addresses the need for robust authorization mechanisms in web applications.