CVE-2005-0785 in YaBB
Summary
by MITRE
Cross-site scripting (XSS) vulnerability in usersrecentposts in YaBB 2.0 rc1 allows remote attackers to inject arbitrary web script or HTML via the username parameter.
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Analysis
by VulDB Data Team • 05/30/2019
The CVE-2005-0785 vulnerability represents a critical cross-site scripting flaw discovered in the YaBB 2.0 rc1 bulletin board system, specifically within the usersrecentposts component. This vulnerability falls under the CWE-79 category of Cross-Site Scripting, which is a fundamental web application security weakness that allows attackers to inject malicious client-side scripts into web pages viewed by other users. The vulnerability manifests when the application fails to properly sanitize user input, particularly in the username parameter that is processed by the usersrecentposts functionality.
The technical flaw occurs because the YaBB 2.0 rc1 software does not adequately validate or escape user-supplied input before incorporating it into dynamic web page content. When a user submits a username containing malicious script code through the affected parameter, the application directly embeds this unfiltered input into the HTML output without proper sanitization measures. This creates an environment where attackers can execute arbitrary JavaScript code within the context of other users' browsers, potentially leading to session hijacking, credential theft, or redirection to malicious websites. The vulnerability specifically targets the username parameter, making it particularly dangerous as usernames are often displayed prominently in forum interfaces and user lists.
The operational impact of this vulnerability extends beyond simple script execution, as it can be leveraged for sophisticated attacks within the forum environment. Attackers can craft malicious usernames containing XSS payloads that will execute whenever other users view the affected pages, potentially compromising user sessions through cookie theft or redirecting users to phishing sites. The vulnerability affects the entire YaBB community by undermining the trust users place in the forum's content and potentially allowing attackers to manipulate forum behavior, post malicious content, or gain unauthorized access to user accounts. Given that YaBB was widely used in 2005, this vulnerability could have impacted numerous online communities and discussion platforms that relied on this software.
Mitigation strategies for CVE-2005-0785 should focus on implementing proper input validation and output encoding mechanisms as recommended by the OWASP Top Ten security practices. Organizations should immediately upgrade to patched versions of YaBB or implement proper HTML escaping for all user-generated content before rendering it on web pages. The solution involves sanitizing all input parameters, particularly those used in dynamic content generation, and implementing Content Security Policy headers to limit script execution capabilities. This vulnerability demonstrates the critical importance of input validation in web applications and aligns with ATT&CK technique T1203 for Exploitation for Client Execution, where attackers leverage XSS vulnerabilities to execute malicious code in user browsers. The remediation process should include comprehensive code review to identify similar input handling issues and implementation of proper security controls to prevent future occurrences of such vulnerabilities.