CVE-2006-2231 in Big Webmaster Guestbook Script
Summary
by MITRE
Multiple cross-site scripting (XSS) vulnerabilities in addguest.cgi in Big Webmaster Guestbook Script 1.02 and earlier allow remote attackers to inject arbitrary web script or HTML via the (1) mail, (2) site, (3) city, (4) state, (5) country, and possibly (6) name fields, which are viewed via viewguest.cgi.
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Analysis
by VulDB Data Team • 09/07/2017
The CVE-2006-2231 vulnerability represents a critical cross-site scripting flaw in the Big Webmaster Guestbook Script version 1.02 and earlier, demonstrating a fundamental weakness in input validation and output sanitization within web applications. This vulnerability affects the addguest.cgi script which processes guestbook entries, creating a persistent security risk that can be exploited by remote attackers to inject malicious scripts into the application's user interface. The vulnerability specifically targets multiple input fields including mail, site, city, state, country, and potentially name fields, all of which are processed and subsequently displayed through the viewguest.cgi script, creating a direct pathway for malicious code execution.
The technical implementation of this vulnerability stems from inadequate sanitization of user-supplied input data before it is rendered in the web interface. When users submit guestbook entries through addguest.cgi, the application fails to properly validate or escape special characters in the submitted fields, allowing attackers to embed malicious javascript code or html elements that will execute in the context of other users' browsers. This type of vulnerability falls under CWE-79 which specifically addresses Cross-Site Scripting vulnerabilities, and represents a classic example of how insufficient input filtering can lead to widespread client-side exploitation. The vulnerability is particularly dangerous because it affects multiple data fields within the same processing script, amplifying the potential attack surface and making it more likely that an attacker can successfully inject malicious content.
The operational impact of CVE-2006-2231 extends beyond simple data corruption or display issues, as it enables attackers to perform various malicious activities through the compromised guestbook application. Successful exploitation could allow attackers to steal session cookies, redirect users to malicious websites, deface the guestbook interface, or even execute more sophisticated attacks such as credential harvesting or browser-based malware delivery. The vulnerability creates a persistent threat because once malicious code is injected into the guestbook entries, it will be executed every time other users view the entries through viewguest.cgi, potentially affecting numerous visitors over extended periods. This makes the vulnerability particularly concerning for websites that rely heavily on user-generated content and social interaction features.
Mitigation strategies for CVE-2006-2231 should focus on implementing comprehensive input validation and output encoding mechanisms to prevent malicious code injection. Organizations should immediately upgrade to a patched version of the Big Webmaster Guestbook Script if available, or implement proper input sanitization techniques that escape special characters before processing user data. The solution should include implementing strict validation of all input fields to ensure they conform to expected formats and character sets, while also employing output encoding when displaying user-supplied content to prevent script execution. Security measures should align with industry best practices and standards such as those outlined in the OWASP Top Ten and the ATT&CK framework, particularly focusing on mitigating web application vulnerabilities through proper input handling and output encoding. Additionally, implementing proper access controls and monitoring for unusual patterns in guestbook submissions can help detect potential exploitation attempts and provide early warning of active attacks against the vulnerable system.