CVE-2015-6995 in Mac OS X
Summary
by MITRE
The Disk Images component in Apple iOS before 9.1 and OS X before 10.11.1 misparses images, which allows attackers to execute arbitrary code or cause a denial of service (memory corruption) via a crafted app.
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Analysis
by VulDB Data Team • 12/31/2024
The vulnerability identified as CVE-2015-6995 resides within Apple's Disk Images component that governs how the operating system handles disk image files such as those with .dmg extensions. This flaw exists in iOS versions prior to 9.1 and OS X versions prior to 10.11.1, representing a critical security gap that affects millions of devices worldwide. The vulnerability stems from improper parsing of disk image files, which creates opportunities for malicious actors to exploit the system through carefully crafted applications that manipulate the image parsing logic.
The technical flaw manifests as a memory corruption issue that occurs when the Disk Images component processes malformed or specially constructed disk image files. This misparsing behavior creates buffer overflows or other memory-related anomalies that can be leveraged by attackers to gain unauthorized code execution privileges. The vulnerability specifically targets the way the system handles image metadata and file structures, allowing an attacker to inject malicious code that executes with the privileges of the affected application. This memory corruption vulnerability falls under the CWE-121 CWE category, which deals with stack-based buffer overflow conditions, and represents a classic example of how improper input validation can lead to arbitrary code execution.
The operational impact of this vulnerability is severe as it provides attackers with a pathway to achieve remote code execution on affected systems without requiring user interaction beyond opening a maliciously crafted application. This means that simply encountering a specially designed disk image file could compromise a device, making it particularly dangerous in environments where users might encounter untrusted applications or files. The vulnerability can be exploited through various attack vectors including email attachments, web downloads, or malicious applications distributed through official app stores, potentially leading to full system compromise, data exfiltration, or persistent backdoor installations.
Organizations and individual users affected by CVE-2015-6995 should immediately apply the security patches released by Apple as part of iOS 9.1 and OS X 10.11.1 updates. The mitigation strategy involves not only updating to the patched versions but also implementing additional security measures such as sandboxing applications that handle disk images, restricting user privileges when opening unknown files, and deploying network monitoring solutions to detect potential exploitation attempts. From an ATT&CK framework perspective, this vulnerability maps to techniques involving privilege escalation and code injection, specifically targeting the T1059.001 and T1068 tactics. The vulnerability also aligns with the broader category of T1203 in ATT&CK, which covers exploitation for privilege escalation through memory corruption issues. System administrators should also consider implementing application whitelisting policies and regular security audits to prevent exploitation of similar vulnerabilities in the future.