CVE-2011-3864 in The Erudite
Summary
by MITRE
Cross-site scripting (XSS) vulnerability in the The Erudite theme before 2.7.9 for WordPress allows remote attackers to inject arbitrary web script or HTML via the cpage parameter.
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Analysis
by VulDB Data Team • 01/16/2018
The CVE-2011-3864 vulnerability represents a classic cross-site scripting flaw that affected the Erudite theme for WordPress installations prior to version 2.7.9. This vulnerability resides within the theme's handling of user-supplied input through the cpage parameter, creating a significant security risk for WordPress users who relied on this particular theme. The flaw demonstrates how seemingly minor input validation issues can lead to substantial security implications when exploited by malicious actors.
The technical nature of this vulnerability stems from inadequate sanitization of the cpage parameter within the Erudite theme's code execution flow. When users navigated to pages that utilized this parameter, the theme failed to properly escape or validate the input before rendering it in the web page context. This lack of proper input filtering allowed attackers to inject malicious scripts or HTML content that would execute in the browsers of unsuspecting visitors. The vulnerability operates under CWE-79 which specifically addresses Cross-Site Scripting flaws, making it a direct descendant of well-known web application security weaknesses that have plagued the industry for decades.
The operational impact of this vulnerability extends beyond simple script injection, as it provides attackers with the capability to perform various malicious activities including session hijacking, defacement of web pages, redirection to malicious sites, and potential data exfiltration from user browsers. An attacker could craft a malicious URL containing the cpage parameter with embedded JavaScript that would execute whenever a victim visited the affected WordPress site. This could lead to unauthorized access to user sessions, modification of site content, or redirection to phishing sites that could harvest sensitive information from authenticated users.
The vulnerability's exploitation requires minimal technical sophistication, making it particularly dangerous as it could be leveraged by attackers with basic web security knowledge. The fact that this affected a popular WordPress theme means that numerous websites were potentially exposed, especially those that had not yet updated to the patched version 2.7.9. Organizations using WordPress with the Erudite theme were at risk of having their sites compromised, potentially leading to reputational damage, loss of user trust, and potential regulatory compliance issues. This vulnerability aligns with ATT&CK technique T1566 which covers the exploitation of web applications through various injection techniques.
Mitigation strategies for CVE-2011-3864 required immediate implementation of the official patch released by the theme developers, which involved proper input sanitization and output encoding of the cpage parameter. Organizations should have conducted thorough security assessments to identify all instances of the vulnerable theme and ensured timely updates were applied across their WordPress installations. Additional defensive measures included implementing content security policies, monitoring for suspicious URL parameters, and conducting regular security audits of web applications. The vulnerability highlighted the critical importance of maintaining up-to-date third-party components and themes in WordPress environments, as outdated plugins and themes continue to represent significant attack vectors in the modern threat landscape.