CVE-2006-3295 in Open Guestbook
Summary
by MITRE
Cross-site scripting (XSS) vulnerability in header.php in Open Guestbook 0.5 allows remote attackers to inject arbitrary web script or HTML via the title parameter.
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Analysis
by VulDB Data Team • 09/16/2017
The CVE-2006-3295 vulnerability represents a classic cross-site scripting flaw in the Open Guestbook 0.5 web application that fundamentally undermines user security through improper input validation. This vulnerability specifically targets the header.php component of the application, where the title parameter fails to properly sanitize user-supplied input before rendering it within the web page context. The flaw enables remote attackers to inject malicious scripts or HTML code that executes in the victim's browser when the affected page is loaded, creating a persistent security risk for all users interacting with the guestbook application. The vulnerability exists due to the application's lack of input filtering mechanisms that would normally prevent malicious code from being executed within the browser context.
The technical implementation of this XSS vulnerability stems from the application's failure to employ proper output encoding or input validation when processing the title parameter. When users submit entries to the guestbook, the title field is directly incorporated into the HTML output without adequate sanitization, allowing attackers to embed script tags or other malicious HTML elements that get executed in the context of other users' browsers. This type of vulnerability falls under CWE-79 which specifically addresses Cross-site Scripting flaws in web applications, where the application fails to properly validate or encode user-provided data before incorporating it into dynamically generated web content. The vulnerability is particularly dangerous because it operates at the presentation layer where user input is rendered as web content, making it an ideal vector for session hijacking, credential theft, and other malicious activities.
The operational impact of CVE-2006-3295 extends beyond simple data corruption or display issues, as it provides attackers with the capability to manipulate the guestbook's user interface and potentially access sensitive information. An attacker could craft malicious entries that redirect users to phishing sites, steal session cookies, or inject malicious advertisements into the guestbook interface. The vulnerability affects all users who view the guestbook entries, making it a widespread threat that can compromise multiple user sessions simultaneously. This type of vulnerability is classified under the ATT&CK framework's T1566 technique for "Phishing" and T1531 for "Account Access Removal", as it enables attackers to establish persistent access to user accounts through session manipulation and credential theft. The attack vector is particularly insidious because it requires minimal technical expertise to exploit, making it a popular target for automated attacks and script kiddies.
The recommended mitigation strategies for this vulnerability involve implementing comprehensive input validation and output encoding mechanisms throughout the application's codebase. Developers should sanitize all user input by removing or encoding potentially dangerous characters such as angle brackets, script tags, and other HTML entities before processing or storing the data. The application should implement proper HTML escaping when rendering user-provided content, ensuring that any special characters are converted to their HTML entity equivalents. Additionally, implementing a Content Security Policy (CSP) header would provide an additional layer of protection by restricting the sources from which scripts can be executed within the application context. The vulnerability demonstrates the critical importance of following secure coding practices and adhering to the principle of least privilege in web application development, where all user input should be treated as potentially malicious and properly validated before any processing occurs. Organizations should also implement regular security audits and penetration testing to identify similar vulnerabilities in legacy applications that may have been overlooked during initial development phases.