CVE-2016-4707 in macOS
Summary
by MITRE
CFNetwork in Apple iOS before 10 and OS X before 10.12 mishandles Local Storage deletion, which allows local users to discover the visited web sites of arbitrary users via unspecified vectors.
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Analysis
by VulDB Data Team • 09/20/2022
The vulnerability identified as CVE-2016-4707 resides within Apple's CFNetwork framework, which serves as the core networking library for iOS and macOS operating systems. This flaw specifically affects versions prior to iOS 10 and OS X 10.12, creating a significant privacy and security risk for users of these older systems. The issue manifests in how the framework handles local storage deletion processes, creating unintended information disclosure channels that could be exploited by malicious actors.
The technical root cause of this vulnerability involves improper handling of local storage cleanup operations within CFNetwork's implementation. When web browsers or applications delete local storage data, the system should ensure complete removal of all associated information. However, in affected Apple operating systems, the deletion process fails to properly overwrite or securely remove cached data, leaving residual information accessible through unspecified vectors. This flaw operates at the system level rather than application level, making it particularly concerning as it affects the underlying network infrastructure rather than specific applications.
The operational impact of CVE-2016-4707 represents a serious privacy breach that could enable attackers to reconstruct browsing histories of arbitrary users on compromised systems. Local users with access to affected devices could exploit this vulnerability to discover which websites other users had visited, potentially exposing sensitive information about personal interests, business activities, or confidential online behaviors. This type of information disclosure aligns with attack patterns described in the ATT&CK framework under the Information Discovery tactic, specifically targeting browser and web application artifacts that reveal user behavior patterns. The vulnerability creates a persistent information leak that could be exploited for social engineering attacks, targeted phishing campaigns, or corporate espionage.
This weakness maps to CWE-200, which describes "Information Exposure" in software systems, and demonstrates how improper data handling during deletion processes can create security vulnerabilities. The vulnerability's classification as a local information disclosure issue indicates that exploitation requires local system access but does not require network connectivity or complex attack vectors. Organizations and individuals using affected Apple operating systems face significant risk of privacy violations, as the vulnerability essentially allows for passive reconnaissance of user browsing patterns without requiring sophisticated attack techniques. The impact extends beyond individual privacy concerns to potential corporate security implications where sensitive business information could be inadvertently exposed through this mechanism. Remediation requires updating to supported versions of iOS and macOS where Apple has patched this specific local storage handling issue, ensuring proper secure deletion mechanisms are implemented throughout the CFNetwork framework.