CVE-2024-40842 in macOS
Summary
by MITRE • 09/17/2024
An issue was addressed with improved validation of environment variables. This issue is fixed in macOS Sequoia 15. An app may be able to access user-sensitive data.
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Analysis
by VulDB Data Team • 09/24/2024
This vulnerability represents a critical security flaw in macOS Sequoia 15 that stems from inadequate validation of environment variables within the operating system's runtime environment. The issue manifests when applications fail to properly validate or sanitize environment variables, potentially allowing malicious actors to manipulate these variables to gain unauthorized access to sensitive user data. The vulnerability falls under the category of environment variable manipulation attacks that can lead to privilege escalation or data exposure scenarios. According to CWE-20, this represents a weakness where the application uses insecure input handling mechanisms, specifically targeting environment variables that are typically used to configure application behavior and system paths. The flaw enables an attacker to craft malicious environment variable values that could bypass normal access controls and potentially read or modify sensitive user information.
The technical implementation of this vulnerability allows for a form of environment variable injection that can be exploited by applications running with elevated privileges or those that improperly trust environment variable contents. When applications fail to validate environment variables, they may inadvertently execute code or access resources that should be restricted, creating a pathway for data leakage or unauthorized operations. The exploitation typically involves setting environment variables to specific values that trigger unexpected behavior in the application's input handling routines, potentially leading to information disclosure or privilege escalation. This type of vulnerability aligns with ATT&CK technique T1556.001 which covers credential access through environment variable manipulation, and T1068 which involves local privilege escalation through insecure environment handling. The vulnerability affects the core system security model where environment variables are used to pass configuration parameters and system paths between processes.
The operational impact of CVE-2024-40842 extends beyond simple data exposure, as it can potentially enable more sophisticated attacks including session hijacking, privilege escalation, and persistent access to user accounts. Applications that rely on environment variables for configuration or path resolution may become vulnerable to attacks that exploit this validation weakness, particularly those handling sensitive user data or system resources. The vulnerability is particularly concerning in enterprise environments where applications may run with elevated privileges or access to critical system resources. Attackers could leverage this weakness to create persistent backdoors or escalate privileges to gain access to user accounts, system files, or network resources that should be protected. The impact is amplified when considering that environment variables are often used to pass configuration information to applications, making this a critical vector for attackers seeking to manipulate application behavior and access sensitive resources.
Mitigation strategies for this vulnerability require immediate patching of affected systems to the latest macOS Sequoia 15 release which includes the necessary validation improvements for environment variables. System administrators should implement comprehensive monitoring for unusual environment variable modifications and establish strict access controls for applications that handle sensitive data. Security teams should conduct vulnerability assessments to identify applications that may be improperly trusting environment variable contents and implement proper input validation routines. The fix addresses the root cause by implementing improved validation mechanisms that ensure environment variables are properly sanitized before being processed by applications. Organizations should also consider implementing application whitelisting policies and runtime application control measures to prevent unauthorized applications from manipulating environment variables. Additional protective measures include regular security audits of environment variable handling code, implementation of secure coding practices, and establishing incident response procedures for potential exploitation attempts. The vulnerability serves as a reminder of the critical importance of proper input validation and the potential consequences of trusting unvalidated system parameters in security-sensitive applications.