CVE-2017-2436 in macOS
Summary
by MITRE
An issue was discovered in certain Apple products. macOS before 10.12.4 is affected. The issue involves the "IOFireWireAVC" component. It allows attackers to execute arbitrary code in a privileged context or cause a denial of service (memory corruption) via a crafted app.
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 10/29/2024
The vulnerability identified as CVE-2017-2436 represents a critical security flaw within Apple's macOS operating system affecting versions prior to 10.12.4. This issue resides within the IOFireWireAVC component which handles FireWire audio and video control protocols, specifically targeting the kernel-level subsystem responsible for FireWire device communication. The vulnerability stems from improper input validation and memory handling within the FireWire control interface, creating a pathway for malicious actors to exploit the system's privileged execution environment.
The technical nature of this vulnerability falls under CWE-121, which describes heap-based buffer overflow conditions, and more specifically aligns with CWE-787, representing out-of-bounds write vulnerabilities. Attackers can leverage this flaw by crafting a malicious application that interacts with FireWire devices through the IOFireWireAVC framework. The vulnerability manifests when the system processes malformed FireWire control commands that trigger memory corruption within kernel space, potentially allowing privilege escalation to root level execution. This memory corruption can occur through buffer overflows or use-after-free conditions that compromise the kernel's integrity.
The operational impact of CVE-2017-2436 extends beyond simple privilege escalation, as it provides attackers with the capability to execute arbitrary code with kernel-level privileges. This represents a severe threat vector since FireWire ports are commonly available on laptops and desktop systems, and the attack can be initiated without requiring physical access to the device. The vulnerability enables attackers to bypass traditional security measures, including system integrity protection and code signing enforcement, by operating within the kernel context where such protections are ineffective. This flaw can result in complete system compromise, data exfiltration, persistent backdoor installation, or denial of service conditions that render the system unusable.
From an adversarial perspective, this vulnerability aligns with ATT&CK technique T1068, which describes "Exploitation for Privilege Escalation," and T1059, covering "Command and Scripting Interpreter." The attack surface is particularly concerning because FireWire ports are often left accessible in enterprise environments, and the exploitation requires minimal user interaction beyond running a malicious application. Organizations should implement immediate mitigations including updating to macOS 10.12.4 or later, disabling FireWire interfaces when not required, and monitoring for suspicious kernel activity. The vulnerability also underscores the importance of maintaining current security patches and implementing network segmentation to limit the potential impact of such kernel-level exploits in enterprise environments.