CVE-2005-0741 in YaBB
Summary
by MITRE
Cross-site scripting (XSS) vulnerability in YaBB.pl for YaBB 2.0 RC1 allows remote attackers to inject arbitrary web script or HTML via the username parameter in a usersrecentposts action.
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Analysis
by VulDB Data Team • 06/20/2024
The vulnerability identified as CVE-2005-0741 represents a classic cross-site scripting flaw within the YaBB.pl forum software version 2.0 RC1. This security weakness specifically manifests in the usersrecentposts action where user input is not properly sanitized or validated before being rendered back to web clients. The vulnerability stems from the application's failure to implement adequate input filtering mechanisms for the username parameter, creating an avenue for malicious actors to inject arbitrary web scripts or HTML content into the forum's display mechanisms.
This XSS vulnerability operates under the Common Weakness Enumeration classification of CWE-79, which specifically addresses "Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')". The flaw enables remote attackers to execute malicious code within the context of other users' browsers without their knowledge. When a victim visits a page that contains the malicious payload injected through the username parameter, the script executes in their browser session, potentially leading to session hijacking, credential theft, or redirection to malicious websites. The vulnerability is particularly concerning because it affects a core forum functionality that displays user-generated content, making it accessible to any user who can submit data to the system.
The operational impact of this vulnerability extends beyond simple script execution, as it can be leveraged for more sophisticated attacks within the context of the forum environment. Attackers can craft malicious usernames that, when displayed in the usersrecentposts action, will execute scripts in the browsers of other forum members. This creates a vector for persistent threats where malicious code can be delivered to multiple users simultaneously. The attack can be particularly damaging in environments where forum members trust each other and may not be vigilant about the content they encounter. The vulnerability also aligns with ATT&CK technique T1566.001, which covers "Phishing: Spearphishing Attachment", as attackers can use the forum platform to deliver malicious payloads through seemingly legitimate user interactions.
Mitigation strategies for CVE-2005-0741 should focus on implementing proper input validation and output encoding mechanisms. The primary defense involves sanitizing all user input, particularly the username parameter, by removing or encoding potentially dangerous characters such as angle brackets, script tags, and JavaScript event handlers. The application should implement strict input validation that rejects or sanitizes any input containing suspicious patterns. Additionally, proper output encoding should be implemented when displaying user-generated content, ensuring that any special characters are properly escaped before rendering in HTML contexts. Organizations should also consider implementing Content Security Policy (CSP) headers to add an additional layer of protection against XSS attacks. The most effective long-term solution involves upgrading to patched versions of YaBB.pl or migrating to more modern forum platforms that have robust XSS protection mechanisms built into their core architecture.