CVE-2011-0180 in Mac OS X
Summary
by MITRE
Integer overflow in HFS in Apple Mac OS X before 10.6.7 allows local users to read arbitrary (1) HFS, (2) HFS+, or (3) HFS+J files via a crafted F_READBOOTSTRAP ioctl call.
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Analysis
by VulDB Data Team • 11/23/2024
The vulnerability identified as CVE-2011-0180 represents a critical integer overflow flaw within the HFS file system implementation of Apple Mac OS X operating systems prior to version 10.6.7. This issue resides in the kernel-level file system handling mechanisms that govern how the operating system processes file system operations, particularly those related to bootstrap file access. The vulnerability specifically affects the HFS, HFS+, and HFS+J file system types, which are commonly used across various Apple operating system versions and hardware configurations. The integer overflow occurs when processing a crafted F_READBOOTSTRAP ioctl system call, which is a specialized interface designed for reading bootstrap information from file systems. This particular ioctl command is typically used for low-level file system operations and is not commonly accessed by regular user applications, making the vulnerability particularly insidious as it can be exploited by local users with minimal privileges.
The technical exploitation of this vulnerability leverages the integer overflow condition to manipulate memory pointers and file access controls within the kernel space. When a malicious local user crafts a specific F_READBOOTSTRAP ioctl call with manipulated parameters, the integer overflow causes the system to misinterpret file access boundaries and potentially bypass normal file system security restrictions. This flaw enables unauthorized reading of arbitrary files from the affected file system types, effectively allowing attackers to access sensitive data that should normally be protected by the file system's access control mechanisms. The vulnerability's classification as a CWE-190 integer overflow aligns with the standard weakness category for issues involving signed integer overflows, where the system's handling of integer values leads to unexpected behavior in memory management and access control. The exploitation requires local system access and leverages the kernel's file system handling routines to achieve privilege escalation and information disclosure.
From an operational impact perspective, this vulnerability poses significant security risks to Mac OS X systems running versions prior to 10.6.7, as it allows local attackers to gain unauthorized access to potentially sensitive files stored on HFS file systems. The ability to read arbitrary files from different HFS variants means that attackers could potentially access configuration files, user data, system logs, or other sensitive information that might contain credentials, personal data, or system configuration details. The vulnerability's exploitation does not require network access or remote execution capabilities, making it particularly dangerous in environments where local access is possible, such as shared computing environments, compromised systems, or insider threat scenarios. Security analysts categorize this vulnerability under the ATT&CK framework's privilege escalation and credential access tactics, as it provides a mechanism for local users to bypass normal file system access controls and gain access to restricted data. The impact extends beyond simple information disclosure, as the ability to read arbitrary files can potentially lead to further exploitation opportunities, including the discovery of system vulnerabilities, credential theft, or the identification of other security weaknesses within the operating system.
The recommended mitigation strategies for CVE-2011-0180 primarily focus on immediate system updates and patch management procedures. Apple released security updates for Mac OS X 10.6.7 that addressed this specific integer overflow vulnerability by implementing proper bounds checking and input validation for the F_READBOOTSTRAP ioctl call. Organizations should prioritize updating their systems to the patched versions of Mac OS X, specifically ensuring that all systems are updated to Mac OS X 10.6.7 or later. Additionally, system administrators should consider implementing network segmentation and access controls to limit local user access where possible, particularly on systems where the vulnerability cannot be immediately patched. Monitoring for suspicious F_READBOOTSTRAP ioctl calls or file access patterns could help detect potential exploitation attempts, though the nature of the vulnerability makes detection challenging due to its low-level kernel operation. The vulnerability demonstrates the critical importance of proper integer handling in kernel-level code and highlights the need for comprehensive input validation and bounds checking in system-level operations, particularly when dealing with file system interfaces that have direct access to system resources and data structures.