CVE-2015-5791 in iTunes
Summary
by MITRE
WebKit, as used in JavaScriptCore in Apple iOS before 9 and iTunes before 12.3, allows remote attackers to execute arbitrary code or cause a denial of service (memory corruption and application crash) via a crafted web site, a different vulnerability than other WebKit CVEs listed in APPLE-SA-2015-09-16-1 and APPLE-SA-2015-09-16-3.
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Analysis
by VulDB Data Team • 06/18/2022
CVE-2015-5791 represents a critical memory corruption vulnerability within WebKit's JavaScriptCore engine that affected Apple iOS versions prior to 9.0 and iTunes versions prior to 12.3. This vulnerability resides in the JavaScriptCore JavaScript engine component of WebKit, which serves as the core rendering and execution engine for web content in Apple's ecosystem. The flaw manifests when processing maliciously crafted web content that triggers undefined behavior in the memory management systems of the JavaScript interpreter. Attackers can exploit this vulnerability by hosting malicious web content that, when loaded in a web browser or web view component, causes the JavaScriptCore engine to corrupt memory structures, leading to arbitrary code execution or application crashes.
The technical nature of this vulnerability stems from improper handling of memory allocation and deallocation within JavaScriptCore's object model management system. When JavaScript objects are created and manipulated, the engine maintains complex memory structures including object headers, property tables, and reference counting mechanisms. The flaw occurs during garbage collection or object reassignment operations where memory pointers become invalid or corrupted, creating opportunities for attackers to manipulate memory layout and execute arbitrary code. This type of vulnerability falls under CWE-125, which describes out-of-bounds read conditions, and CWE-787, which covers out-of-bounds writes, both of which are common in memory corruption vulnerabilities affecting JavaScript engines. The vulnerability can be leveraged through the attack technique of code injection, where malicious payloads are executed within the context of the compromised application.
The operational impact of CVE-2015-5791 extends beyond simple application crashes to represent a full remote code execution capability that could compromise entire user devices. When exploited, this vulnerability allows attackers to gain arbitrary code execution privileges within the context of the affected applications, potentially enabling them to install malicious software, access sensitive user data, or escalate privileges. The vulnerability affects not just web browsers but also any application that utilizes WebKit's JavaScriptCore engine, including iTunes, which means that users could be compromised simply by visiting malicious websites or downloading content through iTunes. This makes the vulnerability particularly dangerous as it requires minimal user interaction to exploit and can be delivered through various attack vectors including phishing websites, malicious advertisements, or compromised web applications. The attack surface is further expanded because JavaScriptCore is used in numerous Apple applications, creating multiple potential entry points for adversaries.
Mitigation strategies for CVE-2015-5791 primarily focus on immediate system updates and application patches provided by Apple. Users must upgrade to iOS 9.0 or later versions and iTunes 12.3 or later to receive the security fixes that address the memory corruption issues in JavaScriptCore. System administrators should implement comprehensive patch management policies to ensure all affected devices are updated promptly, as the vulnerability can be exploited remotely without user interaction. Network-level defenses can include implementing web content filtering solutions and monitoring for suspicious web traffic patterns, though these measures provide only partial protection since the vulnerability can be exploited through various delivery mechanisms. The vulnerability aligns with several ATT&CK techniques including T1059 for command and scripting interpreter and T1068 for exploit for privilege escalation, making it particularly dangerous in environments where users may have elevated privileges. Organizations should also consider implementing additional security controls such as application sandboxing, regular security assessments of web applications, and user education about safe browsing practices to reduce the risk of exploitation.