CVE-2011-0048 in Bugzilla
Summary
by MITRE
Bugzilla before 3.2.10, 3.4.x before 3.4.10, 3.6.x before 3.6.4, and 4.0.x before 4.0rc2 creates a clickable link for a (1) javascript: or (2) data: URI in the URL (aka bug_file_loc) field, which allows remote attackers to conduct cross-site scripting (XSS) attacks against logged-out users via a crafted URI.
If you want to get the best quality for vulnerability data then you always have to consider VulDB.
Analysis
by VulDB Data Team • 10/13/2021
The vulnerability described in CVE-2011-0048 represents a critical cross-site scripting flaw in the Bugzilla bug tracking system that affects multiple versions including 3.2.10, 3.4.10, 3.6.4, and 4.0rc2. This issue stems from the application's insufficient input validation and sanitization mechanisms when processing the bug_file_loc field, which is designed to store external URL references associated with bug reports. The vulnerability allows remote attackers to inject malicious URIs that can execute arbitrary code in the context of a victim's browser, particularly targeting logged-out users who may inadvertently click on these crafted links.
The technical flaw manifests when the Bugzilla application fails to properly validate or sanitize user-supplied URLs that contain javascript: or data: URI schemes within the bug_file_loc field. These URI schemes are inherently dangerous as they allow execution of JavaScript code directly within the browser context without proper security boundaries. When a user views a bug report containing such malicious links, the browser interprets the javascript: or data: URI as executable content rather than a simple URL, leading to potential code execution and session hijacking. This vulnerability directly maps to CWE-79, which describes Cross-Site Scripting vulnerabilities, and specifically aligns with ATT&CK technique T1059.007 for JavaScript execution within web applications.
The operational impact of this vulnerability is significant as it enables attackers to conduct sophisticated XSS attacks against Bugzilla users, particularly those who are not authenticated. Attackers can craft malicious bug reports with javascript: or data: URIs that execute malicious payloads when users view the bug details, potentially stealing session cookies, redirecting users to malicious sites, or performing unauthorized actions within the Bugzilla application. The vulnerability affects both authenticated and unauthenticated users since the malicious links can be crafted to target logged-out users who may view public bug reports. This creates a persistent threat vector that can be exploited through social engineering, where attackers submit malicious bug reports that appear legitimate to unsuspecting users.
Organizations using affected versions of Bugzilla should immediately implement multiple layers of mitigation strategies to protect against this vulnerability. The primary remediation involves upgrading to patched versions of Bugzilla where input validation has been strengthened to reject javascript: and data: URI schemes in the bug_file_loc field. Additionally, administrators should implement Content Security Policy headers that restrict the execution of inline scripts and limit the sources from which scripts can be loaded. Input sanitization measures should be enhanced to properly validate all user-supplied URLs and strip or encode dangerous URI schemes before they are rendered in the user interface. Network-level protections such as web application firewalls can provide additional defense-in-depth, though the most effective solution remains the application-level patching and proper input validation as recommended by OWASP guidelines for preventing XSS vulnerabilities.