CVE-2014-1261 in Mac OS X
Summary
by MITRE
Integer signedness error in CoreText in Apple OS X before 10.9.2 allows remote attackers to execute arbitrary code or cause a denial of service (application crash) via a crafted Unicode font.
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Analysis
by VulDB Data Team • 04/12/2025
The vulnerability identified as CVE-2014-1261 represents a critical integer signedness error within CoreText, Apple's text rendering framework that is integral to the operating system's handling of typography and font management. This flaw exists in Apple OS X versions prior to 10.9.2 and specifically impacts how the system processes Unicode font files, creating a pathway for malicious actors to exploit the system through carefully crafted font data. The vulnerability falls under the category of software security flaws that can lead to arbitrary code execution or system instability, making it particularly dangerous in environments where users might encounter untrusted font content.
The technical root cause of this vulnerability stems from improper handling of signed and unsigned integer values within CoreText's font parsing routines. When processing Unicode font files, the system fails to correctly validate the signedness of integer values used in font structure parsing, leading to potential buffer overflows or memory corruption conditions. This type of error is classified as a CWE-190 - Integer Overflow or Wraparound, which is a common class of vulnerabilities in systems that do not properly validate integer operations. The signedness error specifically manifests when the application attempts to perform operations on values that should be treated as unsigned but are processed as signed, creating a scenario where legitimate font data can trigger unexpected behavior in the system's memory management.
The operational impact of CVE-2014-1261 extends beyond simple application crashes to potentially enable full system compromise through remote code execution. Attackers can craft malicious Unicode font files that, when processed by the vulnerable CoreText framework, cause the system to execute arbitrary code with the privileges of the affected application. This vulnerability is particularly concerning because font files are commonly encountered in legitimate user workflows, making exploitation more likely through social engineering or automated attacks. The vulnerability can be triggered through various attack vectors including email attachments, web content, or file downloads, making it a significant threat to both individual users and enterprise environments where font handling is common.
From an attack perspective, this vulnerability aligns with the MITRE ATT&CK framework's techniques for privilege escalation and execution through malicious files. The attack chain typically involves delivering a crafted Unicode font to a target system, which then gets processed by CoreText during normal system operations, leading to either a denial of service or remote code execution. The vulnerability demonstrates how seemingly benign system components like font rendering can become attack surfaces when proper input validation is lacking. Organizations should implement comprehensive patch management strategies to address this vulnerability, as the remediation requires updating to Apple OS X 10.9.2 or later versions that contain the necessary fixes to properly handle signedness in integer operations within CoreText.
The broader implications of this vulnerability highlight the importance of proper input validation and integer handling in system components that process untrusted data. Security professionals should consider this vulnerability when conducting risk assessments for macOS environments, particularly focusing on areas where font processing occurs. The vulnerability also underscores the need for regular security updates and the importance of maintaining current operating system versions to protect against known exploits. Organizations may need to implement additional controls such as restricting font file handling, monitoring for suspicious font-related activity, and ensuring that automatic font installation features are properly configured to minimize exposure to this class of vulnerability.