CVE-2013-5145 in Mac OS X
Summary
by MITRE
kextd in Kext Management in Apple iOS before 7 does not properly verify authorization for IPC messages, which allows local users to (1) load or (2) unload kernel extensions via a crafted message.
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Analysis
by VulDB Data Team • 06/01/2021
The vulnerability identified as CVE-2013-5145 resides within the kextd component of Apple iOS operating systems prior to version 7, representing a critical authorization flaw in the kernel extension management system. This issue specifically affects the Kext Management subsystem which handles the loading and unloading of kernel extensions on iOS devices. The vulnerability stems from insufficient verification mechanisms within the Inter-Process Communication framework that governs how kextd processes authorization requests for kernel extension operations. The flaw enables local attackers to manipulate IPC messages in ways that bypass normal security controls, creating potential pathways for unauthorized kernel extension manipulation.
The technical implementation of this vulnerability exploits a weakness in the authorization validation process within kextd where the system fails to properly authenticate or verify the legitimacy of incoming IPC messages that request kernel extension operations. This authorization gap allows malicious processes running with local privileges to craft specially formatted IPC messages that appear to originate from trusted sources. When kextd processes these crafted messages, it executes the requested kernel extension loading or unloading operations without proper verification of the requesting process's authorization level. The vulnerability specifically targets the kernel extension management interface, which is critical for system security since kernel extensions operate with the highest privilege level and can directly access system resources and memory.
Operationally, this vulnerability presents significant security implications for iOS devices running versions prior to iOS 7, as it allows local attackers to potentially load malicious kernel extensions or unload legitimate ones that may be critical for system security. The impact extends beyond simple privilege escalation since kernel extensions can modify core system behaviors, access sensitive data, and potentially create persistent backdoors. Attackers could leverage this vulnerability to install rootkits, disable security features, or modify system integrity checks that protect against other malicious activities. The local nature of the exploit means that an attacker must already have access to the device, but this access could be gained through various means such as physical access, phishing attacks, or exploitation of other vulnerabilities that provide initial access.
The vulnerability aligns with CWE-284, which addresses improper access control in software systems, and represents a clear violation of the principle of least privilege in kernel extension management. From an ATT&CK framework perspective, this vulnerability maps to techniques involving privilege escalation and persistence mechanisms, as it enables attackers to modify system components at the kernel level. The exploit requires minimal sophistication but can yield maximum impact due to the privileged nature of kernel extension operations. Organizations and users should prioritize upgrading to iOS 7 or later versions where Apple implemented proper authorization checks for IPC messages in kextd. Additional mitigations include implementing strict app sandboxing policies, monitoring for unauthorized kernel extension activity, and maintaining up-to-date security configurations. The vulnerability demonstrates the critical importance of proper authorization validation in system components that handle privileged operations, particularly those involving kernel-level modifications that can fundamentally alter system security posture.