CVE-2015-7009 in Mac OS X
Summary
by MITRE
FontParser in Apple iOS before 9.1 and OS X before 10.11.1 allows remote attackers to execute arbitrary code or cause a denial of service (memory corruption) via a crafted font file, a different vulnerability than CVE-2015-6976, CVE-2015-6977, CVE-2015-6978, CVE-2015-6990, CVE-2015-6991, CVE-2015-6993, CVE-2015-7008, CVE-2015-7010, and CVE-2015-7018.
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Analysis
by VulDB Data Team • 11/19/2024
The vulnerability identified as CVE-2015-7009 represents a critical memory corruption flaw within Apple's FontParser component that affects iOS versions prior to 9.1 and OS X versions prior to 10.11.1. This vulnerability resides in the font processing subsystem that handles various font formats including TrueType, OpenType, and other embedded font types used across Apple's operating systems. The flaw specifically manifests when the system processes malformed or crafted font files, creating a pathway for remote attackers to exploit the memory handling mechanisms within the parsing logic.
The technical implementation of this vulnerability stems from insufficient input validation and memory management within the FontParser module. When a maliciously crafted font file is processed, the parser fails to properly validate the font structure and boundaries, leading to buffer overflows or heap corruption conditions. This memory corruption can be leveraged by attackers to overwrite critical memory locations, potentially allowing arbitrary code execution or system crashes. The vulnerability operates at the kernel level in many cases, making it particularly dangerous as it can bypass user-space protections and directly affect system stability and security.
The operational impact of CVE-2015-7009 extends beyond simple denial of service scenarios to encompass full system compromise capabilities. Attackers can remotely deliver malicious font files through various attack vectors including email attachments, web content, or compromised websites, making this vulnerability particularly dangerous in mobile environments where users frequently interact with untrusted content. The memory corruption can result in system crashes, application instability, or more critically, provide attackers with elevated privileges to execute malicious code with system-level access. This vulnerability aligns with CWE-121, heap-based buffer overflow, and demonstrates characteristics consistent with ATT&CK technique T1059.007 for execution through embedded malicious content.
Mitigation strategies for CVE-2015-7009 primarily focus on immediate system updates and patches provided by Apple to address the specific memory handling issues within FontParser. Organizations should prioritize deployment of iOS 9.1 and OS X 10.11.1 updates that contain the necessary fixes for the font parsing logic. Additionally, network-level controls including web content filtering and email scanning can help prevent delivery of malicious font files to affected systems. System administrators should implement monitoring for unusual system crashes or memory corruption patterns that may indicate exploitation attempts. The vulnerability highlights the importance of robust input validation and memory safety practices, particularly in font processing components that handle untrusted data from diverse sources. Security teams should also consider implementing sandboxing mechanisms for font processing and establishing incident response procedures specifically tailored to address memory corruption vulnerabilities in system libraries.