CVE-2002-1996 in Postnuke
Summary
by MITRE
Cross-site scripting (XSS) vulnerability in PostNuke 0.71 and earlier allows remote attackers to inject arbitrary web script or HTML via the (1) name parameter in modules.php and (2) catid parameter in index.php.
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Analysis
by VulDB Data Team • 07/12/2019
The vulnerability identified as CVE-2002-1996 represents a critical cross-site scripting flaw affecting PostNuke content management systems version 0.71 and earlier. This vulnerability resides in the web application's input validation mechanisms and allows remote attackers to execute malicious scripts within the context of other users' browsers. The flaw manifests through two distinct attack vectors that target different entry points within the application's architecture. The first vector exploits the name parameter within modules.php, while the second targets the catid parameter in index.php, both of which fail to properly sanitize user-supplied input before rendering it in web responses.
The technical implementation of this vulnerability stems from insufficient input validation and output encoding practices within the PostNuke application codebase. When user-provided data is directly incorporated into web page content without proper sanitization, attackers can inject malicious script code that executes in the victim's browser context. This occurs because the application fails to implement proper HTML escaping or encoding mechanisms for parameters that are expected to contain user input. The vulnerability aligns with CWE-79 which specifically addresses cross-site scripting flaws in web applications, where the weakness allows attackers to inject malicious code that can be executed by other users.
From an operational perspective, this vulnerability presents significant security implications for PostNuke installations, as it enables attackers to perform various malicious activities including session hijacking, credential theft, data manipulation, and redirection to malicious websites. The attack can be executed without requiring any privileged access or authentication, making it particularly dangerous for publicly accessible web applications. An attacker could craft malicious URLs containing script payloads that would execute when unsuspecting users browse to affected pages, potentially compromising user sessions and accessing sensitive information. The vulnerability affects the core functionality of the content management system and could lead to complete compromise of user accounts and application integrity.
Mitigation strategies for this vulnerability require immediate implementation of proper input validation and output encoding mechanisms. System administrators should upgrade to PostNuke versions that have addressed this vulnerability, as version 0.72 and later include patches that properly sanitize user input parameters. Additionally, implementing proper HTML escaping for all user-supplied data before rendering in web pages provides defense-in-depth protection. Organizations should also consider deploying web application firewalls that can detect and block malicious script injection attempts. The remediation process should include thorough code review to ensure all parameters are properly validated and encoded, following secure coding practices recommended by the OWASP Top Ten project. This vulnerability demonstrates the critical importance of input validation in web applications and the potential for widespread impact when such protections are inadequate.