CVE-2009-3892 in Bestpractical
Summary
by MITRE
Cross-site scripting (XSS) vulnerability in Best Practical Solutions RT 3.6.x before 3.6.9, 3.8.x before 3.8.5, and other 3.4.6 through 3.8.4 versions allows remote attackers to inject arbitrary web script or HTML via certain Custom Fields.
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Analysis
by VulDB Data Team • 01/23/2019
The vulnerability identified as CVE-2009-3892 represents a critical cross-site scripting flaw affecting the Request Tracker (RT) issue tracking system developed by Best Practical Solutions. This vulnerability specifically impacts versions 3.6.x prior to 3.6.9, 3.8.x prior to 3.8.5, and all versions ranging from 3.4.6 through 3.8.4, making it a widespread issue affecting multiple release branches of the software. The flaw resides within the handling of Custom Fields, which are user-defined data fields that can be added to tickets in the RT system, creating a pathway for malicious actors to execute arbitrary web scripts or HTML code within the context of other users' browsers.
The technical nature of this vulnerability stems from inadequate input sanitization and output encoding within the RT application's Custom Fields implementation. When users create or modify Custom Fields containing unvalidated user input, the system fails to properly escape or filter special characters that could be interpreted as HTML or JavaScript code. This allows attackers to craft malicious payloads that, when rendered in the browser of a victim user, execute in the context of the victim's session with the RT application. The vulnerability is classified as a classic XSS flaw and maps directly to CWE-79: Improper Neutralization of Input During Web Page Generation, which is a fundamental weakness in web application security that has been documented since 2004 and continues to be one of the most prevalent security issues in web applications.
The operational impact of this vulnerability is significant as it provides attackers with a means to compromise user sessions and potentially escalate privileges within the RT environment. An attacker could inject malicious scripts that steal session cookies, redirect users to phishing sites, or execute unauthorized actions within the RT system. The vulnerability particularly affects organizations that rely heavily on RT for issue tracking and collaboration, as it could be exploited to gain unauthorized access to sensitive issue data, manipulate ticket information, or even perform administrative actions if the attacker can gain access to privileged accounts. The remote nature of the attack means that exploitation can occur from anywhere on the internet without requiring physical access to the system or knowledge of internal network structures.
Mitigation strategies for this vulnerability should focus on immediate patching of affected RT versions to the latest available releases that contain the necessary security fixes. Organizations should also implement comprehensive input validation and output encoding mechanisms for all user-provided data, particularly within Custom Fields and other user-editable components of the application. The implementation of Content Security Policy headers can provide an additional layer of defense by restricting the sources from which scripts can be loaded and executed. Security teams should also conduct regular security assessments of web applications to identify similar input validation weaknesses and establish proper sanitization procedures for all user-facing interfaces. This vulnerability aligns with ATT&CK technique T1566.001: Phishing, as attackers could leverage this flaw to deliver malicious payloads through crafted Custom Fields that appear legitimate to users. Organizations should also consider implementing web application firewalls and monitoring for suspicious patterns in user input that might indicate attempted exploitation of similar XSS vulnerabilities.