CVE-2007-1116 in Firefox
Summary
by MITRE
The CheckLoadURI function in Mozilla Firefox 1.8 lists the about: URI as a ChromeProtocol and can be loaded via JavaScript, which allows remote attackers to obtain sensitive information by querying the browser s session history.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 08/20/2018
The vulnerability described in CVE-2007-1116 represents a significant security flaw in Mozilla Firefox version 1.8 that stems from improper handling of URI protocols within the browser's security model. This issue specifically affects the CheckLoadURI function which incorrectly treats the about: URI scheme as a ChromeProtocol, allowing malicious JavaScript code to bypass normal security restrictions and access privileged browser functionality. The flaw exists in the browser's architecture where certain URI schemes that should be restricted from JavaScript execution are inadvertently granted elevated privileges, creating a dangerous pathway for attackers to exploit. This misconfiguration occurs at the protocol handling layer where the browser fails to properly distinguish between trusted internal protocols and those that should remain restricted to prevent unauthorized access to sensitive data.
The technical implementation of this vulnerability exploits the browser's session history access mechanisms through JavaScript execution, enabling attackers to query and retrieve information from the user's browsing session. When JavaScript attempts to load an about: URI, the CheckLoadURI function incorrectly permits this action because it classifies the scheme as a ChromeProtocol, which typically grants elevated privileges to browser internals. This misclassification allows the malicious script to access session history data that should normally be protected from external JavaScript access. The vulnerability specifically leverages the fact that about: URIs can contain sensitive information about user navigation patterns, visited pages, and potentially other session-related data that could be used for tracking or further exploitation. This issue demonstrates a fundamental flaw in Firefox's URI protocol handling and privilege escalation mechanisms, where the browser fails to properly enforce security boundaries between JavaScript execution contexts and privileged internal browser functions.
The operational impact of this vulnerability extends beyond simple information disclosure, as it provides attackers with the capability to perform user tracking and potentially gather intelligence about browsing behavior. Attackers can construct malicious web pages that, when loaded in Firefox 1.8, automatically query the browser's session history to determine what websites users have visited, creating detailed profiles of user activity without their knowledge or consent. This capability directly violates user privacy expectations and can be exploited for targeted advertising, surveillance, or more sophisticated social engineering attacks. The vulnerability is particularly dangerous because it operates entirely within the browser's JavaScript environment, making it difficult to detect and prevent through traditional network security measures. Additionally, this flaw could enable attackers to identify patterns in user behavior that might reveal sensitive information about personal activities, financial habits, or professional interests, effectively creating a covert tracking mechanism that bypasses normal privacy protections.
Mitigation strategies for CVE-2007-1116 require immediate browser updates to patch the CheckLoadURI function and correct the improper classification of about: URIs as ChromeProtocols. Users should upgrade to Firefox versions that properly implement protocol handling security measures and ensure that all browser security patches are applied promptly. Organizations should implement browser security policies that restrict JavaScript execution capabilities and monitor for suspicious activity that might indicate exploitation attempts. The vulnerability aligns with CWE-264, which covers permissions, privileges, and access control issues, and can be categorized under ATT&CK technique T1056.001 for input injection and T1566 for phishing attacks that leverage browser vulnerabilities. Security professionals should also consider implementing web application firewalls and content security policies that can detect and block attempts to access session history data through JavaScript. Regular security assessments and penetration testing should include evaluation of browser protocol handling mechanisms to identify similar vulnerabilities that might exist in other browser components or versions.