CVE-2006-3063 in myPHP Guestbook
Summary
by MITRE
Multiple cross-site scripting (XSS) vulnerabilities in myPHP Guestbook 1.x through 2.0.0-r1 and before 2.0.1 RC5 allow remote attackers to inject arbitrary web script or HTML via the (1) comment, (2) email, (3) homepage, (4) id, (5) name, and (6) text parameters in (a) index.php, the (7) comment, (8) email, (9) homepage, (10) number, (11) name, and (12) text parameters in (b) admin/guestbook.php, and the (13) email, (14) homepage, (15) icq, (16) name, and (17) text parameters in (c) admin/edit.php.
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Analysis
by VulDB Data Team • 09/17/2017
The vulnerability described in CVE-2006-3063 represents a critical cross-site scripting flaw affecting myPHP Guestbook versions 1.x through 2.0.0-r1 and prior to 2.0.1 RC5. This vulnerability stems from inadequate input validation and sanitization mechanisms within the guestbook application's handling of user-supplied data. The flaw exists across multiple parameters and file locations, creating a widespread attack surface that could be exploited by remote attackers to inject malicious web scripts or HTML content into the application's output. The vulnerability affects core user input fields including comment, email, homepage, id, name, and text parameters, as well as administrative functions in guestbook.php and edit.php files, making it particularly dangerous for web applications that rely on user-generated content.
The technical implementation of this vulnerability falls under CWE-79 which specifically addresses Cross-Site Scripting flaws in software applications. The vulnerability operates by failing to properly sanitize or escape user input before rendering it within web pages, allowing attackers to inject malicious payloads that execute in the context of other users' browsers. When users view pages containing the maliciously injected content, their browsers execute the embedded scripts, potentially leading to session hijacking, credential theft, or redirection to malicious websites. The attack vector is particularly insidious because it targets parameters commonly used for guestbook entries, making it difficult for administrators to distinguish between legitimate and malicious content. The vulnerability affects both frontend and backend administrative interfaces, expanding the potential impact beyond simple user interactions to include administrative functions.
The operational impact of CVE-2006-3063 extends far beyond simple data corruption or display issues. Attackers could exploit this vulnerability to steal user sessions, modify guestbook entries, redirect users to phishing sites, or even gain elevated privileges within the application if proper access controls are not in place. The widespread nature of the vulnerability across multiple parameters and files means that even minimal user interaction could result in successful exploitation. This makes the vulnerability particularly dangerous for applications that store sensitive information or rely on user trust, as malicious actors could use the XSS flaw to compromise the integrity of the entire guestbook system. The vulnerability also creates opportunities for attackers to use the application as a platform for launching further attacks against users or the underlying infrastructure.
Mitigation strategies for this vulnerability should include immediate input validation and output sanitization across all user-supplied parameters. The most effective approach involves implementing proper HTML entity encoding and input filtering mechanisms before any user data is processed or displayed. Administrators should upgrade to version 2.0.1 RC5 or later where the vulnerability has been patched, as this represents the first release with proper sanitization measures. Additional protective measures include implementing content security policies, using secure coding practices that validate input against whitelists, and employing web application firewalls to detect and block malicious payloads. The vulnerability demonstrates the importance of following secure coding guidelines and the principle of least privilege in web application development, where all user input should be treated as potentially malicious and properly validated before being rendered to end users. Organizations should also implement regular security assessments and code reviews to identify similar vulnerabilities in legacy applications that may not have been updated to address known security issues.