CVE-2002-2073 in Site Server
Summary
by MITRE
Cross-site scripting (XSS) vulnerability in the default ASP pages on Microsoft Site Server 3.0 on Windows NT 4.0 allows remote attackers to inject arbitrary web script or HTML via the (1) ctr parameter in Default.asp and (2) the query string to formslogin.asp.
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Analysis
by VulDB Data Team • 08/30/2025
The vulnerability identified as CVE-2002-2073 represents a critical cross-site scripting flaw within Microsoft Site Server 3.0 running on Windows NT 4.0 platforms. This vulnerability falls under the CWE-79 category of Cross-Site Scripting and specifically targets the server-side scripting implementation in the default ASP pages. The issue manifests when the application fails to properly sanitize user input parameters before incorporating them into web responses, creating an exploitable condition where malicious scripts can be injected and executed within the context of other users' browsers. The vulnerability affects two primary entry points: the ctr parameter within Default.asp and the query string parameters processed by formslogin.asp, both of which are fundamental components of the authentication and content delivery mechanisms within the Site Server environment.
The technical exploitation of this vulnerability occurs through the manipulation of HTTP request parameters that are directly reflected in the server-generated responses without adequate input validation or output encoding. When an attacker crafts malicious payloads and injects them into the ctr parameter of Default.asp or the query string of formslogin.asp, the server processes these inputs and returns them to the victim's browser without proper sanitization. This creates a persistent XSS vector where the injected script code executes within the victim's browser context, potentially leading to session hijacking, credential theft, or redirection to malicious sites. The vulnerability is particularly dangerous because it affects the core authentication pages of the system, meaning that successful exploitation could allow attackers to compromise user sessions and gain unauthorized access to protected content or administrative functions.
The operational impact of CVE-2002-2073 extends beyond simple script injection, as it fundamentally undermines the security model of the Site Server application by enabling attackers to execute arbitrary code within user browsers. This vulnerability creates a pathway for attackers to perform session fixation attacks, steal cookies and session tokens, and potentially escalate privileges within the application environment. The attack surface is particularly wide given that these are default pages that handle user authentication and content delivery, making them accessible to all users of the system. The vulnerability also aligns with ATT&CK technique T1531 which involves modifying authentication processes to gain access to systems, and T1059 which encompasses the execution of malicious scripts through web-based interfaces. Organizations running Microsoft Site Server 3.0 on Windows NT 4.0 are particularly at risk since these platforms are legacy systems with limited security updates and support.
Mitigation strategies for this vulnerability must address both immediate remediation and long-term security improvements within the Site Server environment. The most effective immediate solution involves implementing proper input validation and output encoding mechanisms on all user-controllable parameters within the affected ASP pages. This includes sanitizing the ctr parameter in Default.asp and all query string parameters in formslogin.asp to prevent the injection of malicious scripts. Organizations should also implement Content Security Policy headers to limit script execution and establish proper input validation routines that reject or escape potentially dangerous characters. Additionally, the system should be upgraded to a supported version of Microsoft Site Server or migrated to a more modern content management platform, as Windows NT 4.0 and Site Server 3.0 are no longer supported by Microsoft and lack security updates. Network-level protections such as web application firewalls can provide additional layers of defense, while regular security assessments should be conducted to identify similar vulnerabilities in other application components. The vulnerability demonstrates the critical importance of input validation in web applications and serves as a reminder of the security risks inherent in legacy systems that are no longer receiving security updates.