CVE-2012-3743 in iOS
Summary
by MITRE
The System Logs implementation in Apple iOS before 6 does not restrict /var/log access by sandboxed apps, which allows remote attackers to obtain sensitive information via a crafted app that reads log files.
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Analysis
by VulDB Data Team • 04/13/2021
The vulnerability identified as CVE-2012-3743 represents a critical security flaw in Apple iOS versions prior to version 6, specifically within the System Logs implementation. This issue stems from insufficient sandboxing controls that govern access to sensitive system directories, particularly the /var/log filesystem path. The vulnerability exposes a fundamental weakness in iOS's privilege separation model where sandboxed applications can bypass normal access restrictions to read system log files containing sensitive information. This flaw operates under the broader category of improper access control vulnerabilities, which are classified as CWE-284 in the Common Weakness Enumeration catalog and fall under the ATT&CK technique T1074 for data staging and T1083 for file and directory discovery.
The technical implementation of this vulnerability exploits the lack of proper file system access controls within the iOS sandboxing architecture. When applications are sandboxed on iOS, they should normally be restricted from accessing system-level directories and files that contain sensitive operational data. However, the flaw in iOS versions before 6 allowed malicious or crafted applications to directly read files within the /var/log directory structure. This directory typically contains system logs that may include user authentication details, application crash reports, network connection information, and other sensitive operational data that could be valuable to attackers. The vulnerability essentially creates a backdoor through which sandboxed applications can access system logs without proper authorization, undermining the core security principle of least privilege that governs application access in modern mobile operating systems.
The operational impact of this vulnerability extends beyond simple information disclosure, as it provides attackers with potentially valuable intelligence for further exploitation attempts. An attacker who can craft a malicious application that reads system logs can potentially extract user credentials, session tokens, application behavior patterns, and system configuration details that could be used for privilege escalation or targeted attacks against the device or its users. The vulnerability particularly affects iOS versions before 6, which were widely deployed and used across enterprise and consumer environments, making the potential attack surface substantial. This flaw could enable adversaries to perform reconnaissance activities, gather intelligence about system vulnerabilities, and potentially identify weaknesses in user authentication mechanisms or application security implementations. The impact is especially severe given that iOS devices often contain sensitive corporate data, personal information, and credentials that would be valuable targets for cybercriminals.
Mitigation strategies for CVE-2012-3743 primarily focus on upgrading to iOS version 6 or later, where Apple implemented proper sandboxing controls for the /var/log directory access. System administrators should prioritize patching affected devices and implementing mobile device management solutions to ensure comprehensive coverage across enterprise deployments. Additional protective measures include monitoring application behavior for suspicious file access patterns, implementing network-based detection systems to identify potential exploitation attempts, and conducting regular security assessments of mobile applications to ensure they adhere to proper access control practices. Organizations should also consider implementing application whitelisting policies and enhanced monitoring of system log files to detect unauthorized access attempts. The vulnerability highlights the importance of proper sandboxing implementation and access control enforcement in mobile operating systems, aligning with security best practices outlined in various cybersecurity frameworks including NIST SP 800-53 and ISO 27001 standards for information security management.