CVE-2007-4544 in WordPress mu
Summary
by MITRE
Cross-site scripting (XSS) vulnerability in wp-newblog.php in WordPress multi-user (MU) 1.0 and earlier allows remote attackers to inject arbitrary web script or HTML via the weblog_id parameter (Username field).
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Analysis
by VulDB Data Team • 10/29/2017
This cross-site scripting vulnerability exists in WordPress multi-user version 1.0 and earlier installations within the wp-newblog.php script. The flaw specifically affects the handling of the weblog_id parameter which corresponds to the Username field in the user registration process. Attackers can exploit this weakness by injecting malicious web script or HTML code through this parameter, allowing them to execute arbitrary code in the context of other users' browsers. The vulnerability represents a classic stored XSS attack vector where malicious input is processed and stored by the application, then subsequently executed when other users view the affected content. This type of vulnerability falls under CWE-79 which specifically addresses cross-site scripting flaws in software applications. The attack vector operates through the standard web application request processing flow where user input is not properly sanitized or validated before being incorporated into dynamic web page content.
The technical implementation of this vulnerability stems from inadequate input validation and output encoding practices within the WordPress multi-user framework. When the weblog_id parameter is submitted during blog creation, the application fails to properly sanitize the input before rendering it in the HTML output. This allows attackers to inject script tags or other malicious content that gets executed when legitimate users browse to pages containing the compromised data. The vulnerability affects the authentication and registration functionality of WordPress multi-user installations, potentially enabling attackers to steal session cookies, perform unauthorized actions on behalf of users, or redirect victims to malicious websites. The impact is particularly severe in multi-user environments where multiple administrators and contributors interact with the system, as the malicious code could affect any user who views the compromised content.
The operational impact of this vulnerability extends beyond simple script execution to encompass potential privilege escalation and persistent malicious activity within the WordPress environment. An attacker could leverage this vulnerability to establish a foothold within the multi-user system, potentially gaining access to administrative functions or sensitive user data. The attack requires minimal technical expertise to execute successfully, making it particularly dangerous in environments where multiple users interact with the system. This vulnerability aligns with ATT&CK technique T1566 which covers social engineering tactics involving malicious HTML content delivery. The flaw represents a critical security gap in the input handling mechanisms of WordPress MU 1.0 and earlier versions, exposing organizations to potential data breaches and unauthorized access. The vulnerability affects the core authentication and user management functionality of WordPress multi-user installations, compromising the integrity and confidentiality of user data.
Mitigation strategies for this vulnerability involve immediate patching of WordPress multi-user installations to versions that properly sanitize user input and implement proper output encoding. Organizations should ensure all WordPress installations are updated to the latest stable releases that address this specific XSS vulnerability. Input validation should be implemented at multiple layers including client-side and server-side processing to prevent malicious content from being accepted or stored. The application should employ proper output encoding techniques when rendering user-provided data to prevent script execution in web browsers. Security headers including Content Security Policy should be implemented to further mitigate the impact of potential XSS attacks. Regular security audits and input validation testing should be conducted to identify similar vulnerabilities in other parts of the application. Additionally, administrators should implement proper access controls and monitoring to detect suspicious activities that might indicate exploitation attempts. The vulnerability demonstrates the critical importance of proper input sanitization and output encoding in web applications, particularly in multi-user environments where user data integrity is paramount.