CVE-2015-3689

Vulnerability

A memory corruption vulnerability exists in the CoreText component of Apple iOS before 8.4 and OS X before 10.10.4. The issue is triggered when processing a specially crafted text file, leading to memory corruption that can be exploited by an attacker. This vulnerability is distinct from CVE-2015-3685, CVE-2015-3686, CVE-2015-3687, and CVE-2015-3688 [1][2].

Exploitation

To exploit this vulnerability, an attacker must deliver a malicious text file to the target user. The user must then open the crafted file in an application that uses CoreText to render text, such as Safari, Mail, or other text-processing apps. The attack does not require authentication or local access; it can be performed remotely via email, web downloads, or other methods. No additional privileges or user interaction beyond opening the file is required for the exploit to succeed [1][2].

Impact

Successful exploitation allows a remote attacker to execute arbitrary code on the affected device, leading to full device compromise, or cause a denial of service via application crash. The attacker can gain the same privileges as the user running the vulnerable application, potentially allowing access to sensitive data, installation of malware, or other malicious activities. The impact is severe as it affects both mobile and desktop platforms [1][2].

Mitigation

Apple has addressed the vulnerability by releasing iOS 8.4 and OS X Yosemite v10.10.4, along with Security Update 2015-005 for earlier OS X versions. All affected users should update to the latest versions as provided in the official Apple security bulletins [1][2]. No workarounds are available for unpatched systems; as of the advisory, no KEV listing was noted.