CVE-2005-3418 in phpBB
Summary
by MITRE
Multiple cross-site scripting (XSS) vulnerabilities in phpBB 2.0.17 and earlier allow remote attackers to inject arbitrary web script or HTML via the (1) error_msg parameter to usercp_register.php, (2) forward_page parameter to login.php, and (3) list_cat parameter to search.php, which are not initialized as variables.
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Analysis
by VulDB Data Team • 06/11/2019
The vulnerability described in CVE-2005-3418 represents a critical cross-site scripting flaw affecting phpBB versions 2.0.17 and earlier. This issue stems from improper input validation and sanitization within three distinct script files that handle user interactions and error reporting. The vulnerability allows remote attackers to inject malicious web scripts or HTML code into the application's response, potentially compromising user sessions and data integrity. The affected parameters error_msg in usercp_register.php, forward_page in login.php, and list_cat in search.php all fail to properly initialize or sanitize user-provided input before rendering it in the application's output, creating persistent attack vectors that can be exploited across different user interaction points within the forum software.
The technical implementation of this vulnerability aligns with CWE-79 which specifically addresses cross-site scripting vulnerabilities where untrusted data is incorporated into web pages without proper validation or encoding. The flaw occurs because these parameters are directly incorporated into HTML output without adequate sanitization measures, allowing attackers to inject malicious payloads that execute in the context of other users' browsers. The lack of variable initialization creates a condition where user-supplied data flows directly into the application's response, bypassing any built-in security mechanisms. This particular vulnerability demonstrates poor input handling practices that violate fundamental web application security principles and creates a persistent risk for all users interacting with vulnerable phpBB installations.
The operational impact of CVE-2005-3418 extends beyond simple script injection, as it can enable attackers to perform session hijacking, steal sensitive user information, redirect users to malicious sites, or even modify forum content. Attackers can craft malicious URLs containing script payloads that, when clicked by unsuspecting users, execute in their browsers and potentially compromise their accounts. The vulnerability affects core authentication and search functionalities, making it particularly dangerous as it can be exploited during user registration, login processes, or search operations. This creates a broad attack surface that could allow attackers to gain unauthorized access to user accounts, manipulate forum content, or establish persistent access points within the application environment. The long-term consequences include potential data breaches, reputation damage to forum administrators, and the possibility of these vulnerabilities being used as stepping stones for more sophisticated attacks within compromised networks.
Mitigation strategies for this vulnerability require immediate implementation of input validation and output encoding measures across all affected phpBB installations. System administrators must upgrade to phpBB versions 2.0.18 or later, which contain the necessary patches addressing these XSS vulnerabilities. Additionally, implementing proper parameter initialization and input sanitization techniques should be enforced throughout the application codebase to prevent similar issues from occurring. The security measures should include HTML encoding of all user-supplied input before rendering in web pages, implementing proper content security policies, and establishing comprehensive input validation routines. Organizations should also consider implementing web application firewalls to detect and block suspicious input patterns, while conducting regular security audits to identify potential vulnerabilities in their web applications. These measures align with ATT&CK technique T1566 which focuses on social engineering attacks through malicious web content and highlight the importance of proper input validation as a fundamental security control.