CVE-2002-1729 in Guestbook
Summary
by MITRE
Cross-site scripting vulnerability (XSS) in ASPjar Guestbook 1.00 allows remote attackers to execute arbitrary script as other users via the "web site" parameter in a guestbook message.
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Analysis
by VulDB Data Team • 09/02/2025
The vulnerability identified as CVE-2002-1729 represents a classic cross-site scripting flaw within the ASPjar Guestbook version 1.00 web application. This security weakness resides in the application's handling of user input through the "web site" parameter when submitting guestbook messages. The flaw allows malicious actors to inject arbitrary script code that executes in the context of other users' browsers who view the affected guestbook entries. This type of vulnerability falls under the CWE-79 category of Cross-Site Scripting, which is one of the most prevalent and well-documented web application security issues in the industry.
The technical implementation of this vulnerability stems from insufficient input validation and output encoding within the ASPjar Guestbook application. When users submit guestbook entries containing the "web site" parameter, the application fails to properly sanitize or escape the input before rendering it in the web page context. This lack of proper input sanitization creates an opening for attackers to embed malicious scripts such as javascript code that will execute when other users browse the guestbook. The vulnerability specifically affects the guestbook message display functionality where the web site parameter is directly rendered without appropriate security measures to prevent script injection.
The operational impact of this vulnerability extends beyond simple script execution, as it can enable various malicious activities including session hijacking, credential theft, and redirection to malicious sites. An attacker could craft a guestbook message containing a malicious script that steals cookies or session tokens from users viewing the page, potentially allowing unauthorized access to user accounts. The vulnerability also enables phishing attacks where users might be redirected to fraudulent websites that mimic legitimate services. This type of attack can be particularly damaging in environments where guestbooks are used for business communications or user feedback, as it can compromise the trust relationship between the application and its users while potentially exposing sensitive data through the executed scripts.
Mitigation strategies for this vulnerability should focus on implementing proper input validation and output encoding mechanisms throughout the application. The most effective approach involves sanitizing all user input before rendering it in the web page context, particularly for parameters like the "web site" field that are used in HTML output. This can be achieved through the implementation of strict input validation that rejects potentially dangerous characters and sequences, combined with proper HTML encoding of all dynamic content before display. Additionally, implementing a content security policy can provide an additional layer of protection by restricting the sources from which scripts can be executed. Organizations should also consider updating to patched versions of the ASPjar Guestbook application or migrating to more secure alternatives that properly handle user input. The vulnerability demonstrates the critical importance of input validation and output encoding practices that align with security standards such as those outlined in the OWASP Top Ten and the ATT&CK framework's web application attack patterns, where such vulnerabilities are categorized under the initial access and execution phases of the attack lifecycle.