CVE-2015-7047 in iOS
Summary
by MITRE
The kernel in Apple iOS before 9.2, OS X before 10.11.2, tvOS before 9.1, and watchOS before 2.1 allows local users to gain privileges via a crafted mach message that is misparsed.
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Analysis
by VulDB Data Team • 11/13/2024
The vulnerability identified as CVE-2015-7047 represents a critical privilege escalation flaw within the kernel of Apple's operating systems, affecting iOS versions prior to 9.2, OS X versions prior to 10.11.2, tvOS versions prior to 9.1, and watchOS versions prior to 2.1. This issue stems from improper parsing of mach messages, which are fundamental communication primitives used by the Mach microkernel to facilitate inter-process communication and system service requests. The flaw exists in the kernel's message handling mechanism, specifically in how it processes and validates incoming mach messages from user-space applications.
The technical root cause of this vulnerability lies in the kernel's failure to properly validate the structure and contents of mach messages before processing them. When a malicious application sends a crafted mach message, the kernel's message parser does not adequately verify the message format or enforce proper boundaries, allowing attackers to manipulate the message structure to trigger unintended kernel behavior. This misparsing enables local attackers to exploit the kernel's message handling code path and potentially escalate privileges from user-level to kernel-level execution. The vulnerability is particularly dangerous because it operates within the kernel space where all system security controls are bypassed, making it a prime target for privilege escalation attacks.
The operational impact of CVE-2015-7047 is severe as it allows local attackers to achieve unauthorized privilege escalation without requiring physical access or additional attack vectors. An attacker with a low-privilege user account can leverage this vulnerability to gain kernel-level privileges, effectively bypassing all security restrictions imposed by the operating system. This capability enables malicious actors to perform actions such as arbitrary code execution, file system manipulation, network monitoring, and complete system compromise. The vulnerability is particularly concerning in enterprise environments where users may have legitimate access to systems but could exploit this flaw to escalate their privileges and gain unauthorized access to sensitive data or system resources.
This vulnerability maps to CWE-125 in the Common Weakness Enumeration catalog, which describes out-of-bounds read conditions that can lead to privilege escalation and system compromise. The attack pattern aligns with techniques documented in the MITRE ATT&CK framework under privilege escalation tactics, specifically targeting kernel-level exploitation methods. The vulnerability demonstrates a classic example of improper input validation in kernel space, where the failure to properly parse and validate message structures creates a path for malicious code execution at the most privileged level of the operating system. Apple addressed this issue through kernel security updates that implemented stricter validation of mach message formats and enhanced message parsing routines to prevent the exploitation of malformed message structures.
Mitigation strategies for CVE-2015-7047 primarily involve applying the official security patches released by Apple, which include kernel-level updates that fix the message parsing logic and implement additional validation checks. Organizations should prioritize immediate deployment of these updates across all affected systems to prevent exploitation. Additionally, system administrators should implement monitoring solutions to detect anomalous mach message traffic patterns that could indicate exploitation attempts. Network segmentation and privilege minimization practices can help reduce the potential impact of successful exploitation, though these measures cannot prevent the vulnerability itself. Regular security assessments and kernel integrity monitoring should be implemented to detect any potential attempts to exploit similar weaknesses in the system's kernel components.