CVE-2017-2541 in macOS
Summary
by MITRE
An issue was discovered in certain Apple products. macOS before 10.12.5 is affected. The issue involves the "WindowServer" component. It allows attackers to execute arbitrary code in a privileged context or cause a denial of service (memory corruption) via a crafted app.
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Analysis
by VulDB Data Team • 09/02/2024
The vulnerability identified as CVE-2017-2541 represents a critical security flaw within Apple's macOS operating system affecting versions prior to 10.12.5. This issue resides within the WindowServer component, which serves as the core graphical subsystem responsible for managing window operations, display rendering, and user interface elements. The WindowServer acts as a privileged process that handles direct interaction with graphics hardware and manages the visual presentation of applications, making it a prime target for attackers seeking elevated privileges. The vulnerability stems from improper input validation and memory handling within this critical subsystem, creating an exploitable condition that can be leveraged by malicious actors to gain unauthorized access to system resources.
The technical exploitation of this vulnerability occurs through a crafted application that triggers memory corruption within the WindowServer process. When the malicious application is executed, it manipulates the WindowServer's memory management routines in a way that leads to arbitrary code execution with elevated privileges. This memory corruption can manifest as heap overflow conditions or use-after-free vulnerabilities that allow attackers to overwrite critical memory structures or inject malicious code into the privileged WindowServer process. The flaw operates at the kernel level within the graphics subsystem, meaning that successful exploitation can result in complete system compromise without requiring user interaction beyond launching the malicious application. This type of vulnerability falls under CWE-121, which describes heap-based buffer overflow conditions, and represents a classic privilege escalation vector that can be exploited using techniques aligned with ATT&CK tactic T1068, which covers exploit for privilege escalation.
The operational impact of CVE-2017-2541 extends beyond simple denial of service scenarios, as it provides attackers with persistent access to the system through the WindowServer's privileged execution context. Once exploited, the vulnerability allows adversaries to execute arbitrary code with the highest level of system privileges, potentially enabling them to install malware, modify system files, establish backdoors, or exfiltrate sensitive data without detection. The vulnerability's presence in macOS versions before 10.12.5 means that users running these older operating systems face significant risk, as the WindowServer component is essential for all graphical operations and user interface functionality. Attackers can leverage this vulnerability through social engineering campaigns, phishing emails, or malicious software distribution channels, as the exploitation requires only the execution of a specially crafted application rather than complex multi-stage attacks.
Organizations and individual users must implement immediate mitigations to protect against exploitation of CVE-2017-2541. The primary and most effective mitigation strategy involves updating to macOS version 10.12.5 or later, which contains patches addressing the memory corruption issues within the WindowServer component. System administrators should prioritize deployment of this security update across all affected macOS devices, particularly in enterprise environments where multiple users may be running outdated operating system versions. Additionally, implementing application whitelisting policies can provide an additional layer of defense by preventing execution of untrusted applications that might attempt to exploit this vulnerability. Network monitoring solutions should be configured to detect suspicious application execution patterns and unusual graphics-related system calls that might indicate exploitation attempts. Security teams should also consider implementing automated vulnerability scanning to identify systems running vulnerable macOS versions and ensure timely patch deployment. The vulnerability demonstrates the importance of maintaining current operating system versions and highlights the critical need for regular security updates, as the WindowServer component's privileged nature makes it particularly dangerous when compromised. Organizations should also review their incident response procedures to ensure readiness for potential exploitation attempts, as this vulnerability could be used in targeted attacks against high-value targets or in broader malware campaigns.