CVE-2015-5940 in Mac OS X
Summary
by MITRE
The Accelerate Framework component in Apple iOS before 9.1 and OS X before 10.11.1, when multi-threading is enabled, omits certain validation and locking steps, which allows remote attackers to execute arbitrary code or cause a denial of service (memory corruption) via a crafted web site.
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Analysis
by VulDB Data Team • 06/24/2022
The CVE-2015-5940 vulnerability resides within Apple's Accelerate Framework, a core system component that provides optimized mathematical and scientific computing functions across iOS and macOS platforms. This framework serves as a foundation for numerous applications and system processes that require high-performance numerical operations, making it a critical component in Apple's operating system architecture. The vulnerability specifically manifests when multi-threading is enabled, exposing a fundamental flaw in the framework's concurrency handling mechanisms that affects versions prior to iOS 9.1 and OS X 10.11.1. The flaw represents a significant security weakness that could be exploited by remote attackers to gain unauthorized system access or disrupt service availability.
The technical root cause of this vulnerability stems from inadequate validation and locking mechanisms within the Accelerate Framework's multi-threading implementation. When multiple threads attempt to access shared resources simultaneously, the framework fails to properly synchronize access to critical memory regions, creating race conditions that can result in memory corruption. This memory corruption occurs because the system does not validate input parameters or enforce proper locking protocols before processing multi-threaded requests. The vulnerability is particularly dangerous because it allows attackers to craft malicious web content that, when processed by the affected framework, triggers the race condition and leads to arbitrary code execution or system crashes. This represents a classic concurrency vulnerability that aligns with CWE-362, which describes "Concurrent Execution using Shared Resource with Improper Synchronization," and CWE-119, which addresses "Improper Restriction of Operations within the Bounds of a Memory Buffer."
The operational impact of CVE-2015-5940 extends beyond simple denial of service scenarios to encompass full system compromise potential. Remote attackers can leverage this vulnerability through web browsers or other applications that utilize the Accelerate Framework, making it particularly dangerous in mobile environments where users frequently browse untrusted websites. The memory corruption vulnerability allows for arbitrary code execution, potentially enabling attackers to escalate privileges, install malicious software, or exfiltrate sensitive data from affected devices. This vulnerability directly maps to ATT&CK technique T1059.007, "Command and Scripting Interpreter: JavaScript', as attackers can exploit web-based interfaces to deliver malicious payloads that trigger the framework's flawed concurrency handling. The widespread use of the Accelerate Framework across Apple's ecosystem means that numerous applications and system services could be affected, creating a broad attack surface.
Mitigation strategies for CVE-2015-5940 primarily focus on immediate system updates and configuration changes. Apple's recommended solution involves upgrading to iOS 9.1 or later and OS X 10.11.1 or later, which contain patches that properly implement validation and locking mechanisms within the Accelerate Framework. Organizations should prioritize patch management to ensure all affected systems receive the necessary updates promptly. Additionally, network administrators can implement web filtering solutions to block access to known malicious sites that may exploit this vulnerability. The vulnerability demonstrates the importance of proper concurrency control in system components, highlighting the need for comprehensive security testing of multi-threaded applications and system frameworks. Security professionals should also consider monitoring for unusual system behavior or memory corruption patterns that might indicate exploitation attempts, as the vulnerability's impact can be subtle and difficult to detect without proper forensic tools and monitoring capabilities.