CVE-2016-1746 in Mac OS X
Summary
by MITRE
IOGraphics in Apple OS X before 10.11.4 allows attackers to execute arbitrary code in a privileged context or cause a denial of service (memory corruption) via a crafted app, a different vulnerability than CVE-2016-1747.
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Analysis
by VulDB Data Team • 07/11/2022
The vulnerability identified as CVE-2016-1746 resides within the IOGraphics framework of Apple's macOS operating system, specifically affecting versions prior to 10.11.4. This issue represents a critical security flaw that enables attackers to execute arbitrary code with elevated privileges or potentially cause system instability through memory corruption. The vulnerability operates within the graphics subsystem that handles hardware graphics processing and display management, making it particularly dangerous as it can be triggered through seemingly benign applications. The IOGraphics framework serves as a crucial component in macOS that interfaces with graphics hardware drivers and manages display operations, creating a potential attack surface that can be exploited to gain unauthorized system access.
Technical exploitation of CVE-2016-1746 occurs when a malicious application crafts specific inputs or data structures that trigger memory corruption within the IOGraphics subsystem. This memory corruption can lead to arbitrary code execution in a privileged context, effectively allowing attackers to bypass normal security restrictions and operate with system-level privileges. The vulnerability differs from CVE-2016-1747 in its specific implementation and attack vector, though both represent flaws within the same broader graphics subsystem. The underlying technical flaw typically involves improper input validation or buffer overflow conditions within the graphics processing code that handles device driver interactions and display management operations. This type of vulnerability falls under CWE-121, which describes heap-based buffer overflow conditions, and may also relate to CWE-125, representing out-of-bounds read conditions that can result in memory corruption.
The operational impact of this vulnerability extends beyond simple privilege escalation, as it can be leveraged to establish persistent system access or cause complete system instability through denial of service conditions. Attackers can craft malicious applications that, when executed, trigger the memory corruption within the IOGraphics framework, potentially leading to system crashes or unauthorized code execution. The privileged execution context means that successful exploitation could allow attackers to modify system files, install malware, or access sensitive data without user interaction. This vulnerability is particularly concerning because graphics processing is integral to normal system operation, making the attack surface wide and potentially difficult to detect. The impact aligns with ATT&CK technique T1068, which covers 'Local Privilege Escalation' through exploitation of system vulnerabilities, and T1059, covering 'Command and Scripting Interpreter' as attackers may leverage the elevated privileges to execute further malicious commands.
Organizations and users must implement immediate mitigations to address CVE-2016-1746, with the primary recommendation being the upgrade to macOS version 10.11.4 or later where this vulnerability has been patched. System administrators should conduct comprehensive vulnerability assessments to identify any potentially compromised systems and ensure all endpoints are updated with the latest security patches. Additional mitigations include implementing application whitelisting policies to prevent execution of untrusted applications, monitoring for unusual graphics processing activity, and maintaining robust backup procedures to recover from potential exploitation attempts. The vulnerability highlights the importance of keeping operating systems updated and demonstrates how graphics subsystems can serve as critical attack vectors in modern operating systems. Security monitoring should focus on identifying suspicious memory allocation patterns or graphics processing anomalies that may indicate exploitation attempts, as these systems often require specialized forensic analysis to detect successful attacks.