CVE-2012-3697 in Safari
Summary
by MITRE
WebKit in Apple Safari before 6.0 does not properly handle file: URLs, which allows remote attackers to bypass intended sandbox restrictions and read arbitrary files by leveraging a WebProcess compromise.
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Analysis
by VulDB Data Team • 01/04/2025
The vulnerability identified as CVE-2012-3697 represents a critical sandbox escape flaw within Apple Safari's WebKit rendering engine that existed prior to version 6.0. This issue stems from improper handling of file: URLs which creates a significant security gap in the browser's privilege separation mechanisms. The flaw allows remote attackers to circumvent the intended security boundaries that normally prevent web content from accessing local system resources, effectively breaking down the isolation between web processes and the underlying operating system.
The technical root cause of this vulnerability lies in WebKit's insufficient validation and processing of file:// protocol URLs within the browser's WebProcess execution context. When Safari encounters file: URLs, the implementation fails to properly enforce the security restrictions that should prevent arbitrary file access from web content. This improper handling creates a path for malicious web pages to exploit the WebProcess compromise, enabling attackers to read arbitrary files from the victim's local system. The vulnerability specifically affects the sandboxing mechanisms that are designed to isolate web content execution from the broader system, allowing privilege escalation through the manipulation of file URL handling.
The operational impact of this vulnerability is severe and far-reaching within the context of web browser security. Attackers can leverage this flaw to access sensitive files such as configuration data, user credentials, system logs, and other potentially confidential information stored locally on the victim's machine. The vulnerability essentially transforms a web browser into a tool for local file system reconnaissance and access, bypassing the fundamental security assumptions that users rely on when browsing the internet. This type of attack vector aligns with the attack pattern described in the ATT&CK framework under privilege escalation and defense evasion techniques, where attackers seek to move laterally within compromised systems by exploiting browser security flaws.
From a cybersecurity perspective, this vulnerability demonstrates the critical importance of proper input validation and protocol handling within browser components. The flaw relates to CWE-264, which covers permissions, privileges, and access controls, and specifically addresses issues with improper handling of file system access controls. The vulnerability also intersects with CWE-119, which deals with weaknesses in memory management, as the improper handling of file URLs could potentially lead to memory corruption or buffer overflow conditions. Organizations and users were particularly vulnerable since Safari was widely used across macOS systems, making this a prevalent security concern that affected millions of users and required immediate patching.
The mitigation strategies for this vulnerability primarily involve updating to Safari version 6.0 or later, which includes the necessary fixes to properly handle file: URLs within the WebKit engine. Additionally, system administrators should implement network-level protections such as web application firewalls that can detect and block suspicious file URL patterns, while security teams should monitor for exploitation attempts through threat intelligence feeds. The vulnerability also underscores the need for comprehensive browser security testing and the importance of maintaining current software versions to protect against known security flaws. Organizations should consider implementing additional security measures such as sandboxing at the operating system level and network segmentation to limit the potential impact of similar vulnerabilities in other browser components.