CVE-2009-1706 in Safari
Summary
by MITRE
The Private Browsing feature in Apple Safari before 4.0 on Windows does not remove cookies from the alternate cookie store in unspecified circumstances upon (1) disabling of the feature or (2) exit of the application, which makes it easier for remote web servers to track users via a cookie.
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Analysis
by VulDB Data Team • 09/06/2019
The vulnerability described in CVE-2009-1706 represents a critical flaw in Apple Safari's implementation of private browsing functionality on Windows platforms prior to version 4.0. This security issue directly impacts user privacy and tracking prevention mechanisms that are fundamental to modern web browsers. The flaw specifically affects how Safari handles cookie management during private browsing sessions, creating a persistent tracking vector that undermines the core purpose of private browsing modes. The vulnerability stems from improper cookie cleanup procedures that fail to adequately purge session data when users disable private browsing or terminate the browser application.
The technical implementation flaw manifests in the browser's alternate cookie store management system where cookies intended to be ephemeral during private browsing sessions remain accessible to remote web servers. This occurs due to incomplete cookie removal processes that should have cleared all tracking data when private browsing mode was disabled or when the application exited. The vulnerability creates a persistent tracking mechanism that allows websites to maintain user identification across different browsing sessions, effectively nullifying the privacy protections that private browsing is designed to provide. According to CWE classification, this represents a weakness in the secure removal of sensitive data, specifically categorized under CWE-200 Information Exposure and CWE-312 Cleartext Storage of Sensitive Information.
From an operational impact perspective, this vulnerability significantly undermines user privacy expectations and creates potential for long-term tracking of user behavior across the internet. Attackers can exploit this flaw to maintain persistent identification of users even after they believe they have exited private browsing mode or closed the browser application. The tracking capability extends beyond simple session management to include behavioral profiling, targeted advertising, and potentially more sophisticated surveillance activities. This vulnerability particularly affects users who rely on private browsing modes for sensitive activities such as financial transactions, medical research, or any activity requiring confidentiality. The issue also demonstrates a failure in proper application state management and data lifecycle handling, which aligns with ATT&CK technique T1566 Credential Access through improper session cleanup.
Mitigation strategies for this vulnerability require immediate browser updates to version 4.0 or later where the cookie management system has been properly implemented. Users should disable private browsing mode if they need to maintain strict privacy controls, as the feature was fundamentally flawed in earlier versions. System administrators should ensure all Safari installations on Windows platforms are updated to the patched versions and consider implementing additional monitoring for suspicious cookie behavior patterns. The vulnerability highlights the importance of thorough testing for privacy features and proper implementation of data sanitization procedures. Organizations should also consider deploying network monitoring tools to detect anomalous cookie behavior that might indicate exploitation attempts. Security professionals should be aware that this vulnerability could be leveraged in combination with other tracking techniques to create comprehensive user profiling systems, making it essential to address the root cause through proper software updates and security patch management procedures.