CVE-2005-2262 in Firefox
Summary
by MITRE
Firefox 1.0.3 and 1.0.4, and Netscape 8.0.2, allows remote attackers to execute arbitrary code by tricking the user into using the "Set As Wallpaper" (in Firefox) or "Set as Background" (in Netscape) context menu on an image URL that is really a javascript: URL with an eval statement, aka "Firewalling."
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Analysis
by VulDB Data Team • 06/07/2019
This vulnerability represents a critical cross-site scripting flaw that exploited the trust relationship between web browsers and their users. The issue affected major browser versions including firefox 1.0.3 and 1.0.4, along with netscape 8.0.2, where users could be tricked into executing malicious code through seemingly benign context menu interactions. The attack vector leveraged the legitimate "set as wallpaper" functionality in firefox and "set as background" in netscape, which were designed to allow users to set images as their desktop backgrounds. However, the vulnerability occurred when these context menu options were manipulated to accept javascript: URLs instead of traditional image URLs, allowing attackers to craft malicious image links that would execute arbitrary code upon user interaction. This type of attack falls under the category of user interface deception and privilege escalation through social engineering combined with browser implementation flaws.
The technical implementation of this vulnerability stemmed from inadequate input validation and sanitization within the browser's context menu handlers for image manipulation features. When users right-clicked on an image and selected the wallpaper/background setting option, the browser failed to properly validate the URL type before executing the associated javascript code. This flaw created an environment where javascript: URLs could be processed through the same execution path as regular image URLs, effectively bypassing security boundaries that should have prevented code execution from user-controlled input. The vulnerability specifically targeted the browser's handling of the javascript: protocol within context menu operations, where the security model was not properly enforced to distinguish between legitimate image resources and malicious code injection attempts. The flaw was classified as a type of code injection vulnerability where the execution context was manipulated through user interface elements rather than traditional web form submissions.
The operational impact of this vulnerability was severe as it allowed remote attackers to execute arbitrary code on affected systems without requiring any special privileges or complex exploitation techniques. Users could be tricked into clicking on seemingly innocent image links that would execute malicious javascript code, potentially leading to complete system compromise. The attack required only social engineering to convince users to interact with malicious content, making it particularly dangerous in phishing campaigns and targeted attacks. Successful exploitation could result in data theft, system modification, or complete compromise of the user's browsing environment. The vulnerability was particularly concerning because it exploited the trust users placed in their browser's context menu functionality, which is typically considered a safe operation for setting desktop backgrounds. This type of attack could be easily disguised as legitimate content, making it difficult for users to detect malicious intent.
Mitigation strategies for this vulnerability required both immediate browser patches and user education about the risks of clicking on untrusted content. Browser vendors needed to implement proper URL validation and protocol filtering within context menu handlers to prevent javascript: URLs from being executed through wallpaper/background setting operations. Security updates should have enforced strict content type checking and protocol restrictions for image handling functions, ensuring that only appropriate image resources could be processed through these features. Organizations should have implemented additional security measures such as content filtering and user awareness training to prevent users from inadvertently clicking on malicious links. The vulnerability highlighted the importance of proper input validation and the need for robust security boundaries within user interface components. This incident reinforced industry standards around secure coding practices and the necessity of validating all user inputs regardless of their source or intended use within browser applications. The flaw demonstrated how seemingly innocuous user interface features could become attack vectors when proper security validation was not implemented.