CVE-2006-3953 in MyBB
Summary
by MITRE
Cross-site scripting (XSS) vulnerability in usercp.php in MyBB (aka MyBulletinBoard) 1.x allows remote attackers to inject arbitrary web script or HTML via the gallery parameter.
If you want to get best quality of vulnerability data, you may have to visit VulDB.
Analysis
by VulDB Data Team • 04/30/2019
The vulnerability identified as CVE-2006-3953 represents a critical cross-site scripting flaw within the MyBulletinBoard forum software version 1.x, specifically affecting the usercp.php component. This vulnerability resides in the handling of user input parameters, particularly the gallery parameter, which fails to properly sanitize or validate incoming data before processing. The flaw enables malicious actors to inject arbitrary web scripts or HTML content into the forum's user interface, creating a persistent security risk for all users interacting with the affected system. The vulnerability stems from insufficient input validation and output encoding mechanisms within the MyBB application's user control panel functionality, specifically in how it processes the gallery parameter during user profile management operations.
This XSS vulnerability operates through a classic injection attack vector where an attacker crafts malicious input containing script code within the gallery parameter of the usercp.php script. When the vulnerable application processes this input and displays it back to users without proper sanitization, the injected scripts execute within the context of other users' browsers. The attack can be executed through various methods including direct parameter manipulation, social engineering to trick users into clicking malicious links, or by exploiting the vulnerability in automated attack frameworks targeting MyBB installations. The security implications extend beyond simple script execution as this vulnerability can be leveraged to steal session cookies, perform unauthorized actions on behalf of users, or redirect victims to malicious websites. The vulnerability is classified under CWE-79 as "Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')", which represents one of the most prevalent and dangerous web application security flaws identified by the CWE organization.
The operational impact of CVE-2006-3953 is significant for MyBB installations, as it undermines the trust and security of the entire forum platform. Attackers can exploit this vulnerability to compromise user accounts, steal sensitive information, manipulate forum content, or establish persistent backdoors within the affected environment. The vulnerability affects all users who interact with the forum's user control panel, particularly those who view gallery content or profile information. The attack surface is broad since the gallery parameter is commonly used in user profile management and can be accessed through multiple navigation paths within the application. Organizations running MyBB 1.x systems face potential data breaches, reputation damage, and compliance violations if this vulnerability remains unpatched. The vulnerability also aligns with ATT&CK technique T1566.001 for 'Phishing with Social Engineering' and T1059.007 for 'Command and Scripting Interpreter: JavaScript', demonstrating how this flaw can be weaponized in broader attack campaigns.
Mitigation strategies for CVE-2006-3953 require immediate implementation of input validation and output encoding measures within the MyBB application. The most effective approach involves sanitizing all user-supplied input, particularly the gallery parameter, by removing or encoding potentially dangerous characters before processing. This includes implementing proper HTML entity encoding for output display, validating input against strict whitelists, and employing Content Security Policy headers to prevent script execution. Organizations should also consider upgrading to patched versions of MyBB 1.x, as the vulnerability was addressed in subsequent releases. Network-level protections such as web application firewalls can provide additional defense-in-depth, though they should not replace proper code-level fixes. Security monitoring should include detection of suspicious parameter values in usercp.php requests, and regular security audits should verify that all user input handling mechanisms properly implement sanitization. The vulnerability demonstrates the critical importance of following secure coding practices and implementing comprehensive input validation as outlined in OWASP Secure Coding Practices, particularly the principle of least privilege and proper data sanitization at all input points within web applications.