CVE-2004-0763 in Firefox
Summary
by MITRE
Mozilla Firefox 0.9.1 and 0.9.2 allows remote web sites to spoof certificates of trusted web sites via redirects and Javascript that uses the "onunload" method.
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 12/25/2024
The vulnerability identified as CVE-2004-0763 represents a significant security flaw in Mozilla Firefox versions 0.9.1 and 0.9.2 that undermines the browser's certificate validation mechanisms. This issue specifically exploits the browser's handling of certificate verification during navigation sequences involving redirects and javascript execution. The flaw allows malicious web sites to potentially deceive users into believing they are visiting legitimate trusted sites while actually being redirected to fraudulent destinations. The vulnerability stems from improper certificate validation logic that fails to properly verify certificate chains when javascript events such as onunload are triggered during page navigation. This represents a classic case of inadequate input validation and certificate chain verification that violates fundamental security principles. The technical implementation flaw occurs when the browser processes javascript events during navigation and fails to maintain proper certificate validation context, allowing attackers to manipulate the certificate display during redirect operations. This vulnerability directly relates to CWE-295 which addresses improper certificate validation and CWE-352 which covers cross-site request forgery attacks. The security implications extend beyond simple certificate spoofing to encompass potential man-in-the-middle attack scenarios where users might unknowingly trust malicious certificates. The operational impact of this vulnerability is substantial as it can enable attackers to perform credential theft, data exfiltration, and other malicious activities by making users believe they are communicating with legitimate services. The attack vector leverages the browser's javascript capabilities to manipulate the user interface during navigation events, specifically targeting the certificate verification display mechanism. This attack pattern aligns with ATT&CK technique T1059.007 for JavaScript and T1557.001 for Lateral Movement through web-based attacks. The vulnerability affects users who browse the internet with these specific Firefox versions, particularly when visiting compromised websites or those that have been compromised by attackers. The flaw exists because Firefox does not properly maintain certificate validation state during javascript execution contexts, allowing attackers to exploit the timing and sequence of events during page transitions. The security implications are particularly severe because certificate warnings are fundamental trust indicators in web browsers, and their manipulation can lead to complete trust model compromise. Users may be tricked into entering sensitive information on fraudulent sites that appear to be legitimate, as the certificate warnings are either suppressed or manipulated to appear as if they are from trusted sources. This vulnerability demonstrates the critical importance of maintaining proper security context during complex browser operations involving multiple execution environments and event handlers. The fix for this vulnerability required Firefox to implement more robust certificate validation that properly tracks certificate state throughout navigation sequences, particularly during javascript execution contexts. This type of vulnerability highlights the complexity of modern web browsers and the challenges in maintaining security across multiple execution environments including javascript, html, and network communication layers. The issue underscores the need for comprehensive testing of certificate validation logic under various execution scenarios and event handling conditions. Security researchers have noted that similar vulnerabilities can exist in other browsers that do not properly maintain certificate validation context during complex navigation operations involving javascript execution. The vulnerability also demonstrates the importance of user education about certificate warnings and the potential for social engineering attacks that exploit browser security flaws. Organizations should ensure that all users are updated to Firefox versions that properly address this vulnerability and that security policies include regular browser updates as part of their security maintenance procedures. The mitigation strategy involves both immediate browser updates and ongoing monitoring of browser security patches to prevent exploitation of similar vulnerabilities in the future. This vulnerability serves as a reminder of the critical need for robust certificate validation and proper security context management in web browser implementations. The flaw represents a failure in the browser's security architecture to properly handle certificate validation during complex user interaction scenarios involving javascript and navigation events. The vulnerability's existence emphasizes the need for comprehensive security testing of browser components under realistic usage scenarios that include javascript execution and complex navigation patterns.