CVE-2026-43691 in macOS
Summary
by MITRE • 09/15/2026
A path handling issue was addressed with improved validation. This issue is fixed in macOS Golden Gate 27, macOS Sequoia 15.8, macOS Tahoe 26.7. An app may be able to gain root privileges.
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Analysis
by VulDB Data Team • 09/15/2026
The vulnerability described involves a critical flaw in path handling logic within the operating system's core components, specifically affecting versions of macOS prior to Golden Gate 27, Sequoia 15.8, and Tahoe 26.7. This issue stems from insufficient validation mechanisms when processing file paths or directory structures during privileged operations. In many modern operating systems, path handling is a fundamental aspect of security because it dictates how the system interprets user-supplied input to locate resources on disk. When this logic fails to properly sanitize or validate inputs, attackers can exploit ambiguous interpretations of relative versus absolute paths, symbolic links, or race conditions in directory traversal. The specific nature of this flaw allows an application that does not inherently possess elevated privileges to manipulate these path resolution mechanisms in a way that bypasses standard access controls.
From a technical perspective, the root cause likely involves improper neutralization of special elements within file paths, which aligns with CWE-22: Improper Limitation of a Pathname to a Restricted Directory. This category of vulnerability is particularly dangerous because it often intersects with privilege escalation vectors where an attacker leverages system-level functions that assume safe input without rigorous verification. By crafting specific path sequences or exploiting timing windows in file operations, a malicious application can trick privileged processes into performing actions on unintended files or directories. These unintended targets may include configuration files containing sensitive credentials, binary executables used by the kernel or system services, or other critical components whose modification grants control over the entire system state.
The operational impact of this vulnerability is severe due to its potential for privilege escalation. As noted in the advisory, an app may be able to gain root privileges. Root access represents the highest level of authority on a Unix-based operating system like macOS, providing unrestricted read and write capabilities across all files and processes. Once an attacker achieves root status through this path handling flaw, they can install persistent backdoors, exfiltrate sensitive user data such as passwords or encryption keys, disable security features like Gatekeeper or SIP (System Integrity Protection), and pivot to attack other devices on the local network. This transforms a contained application compromise into a complete system takeover, undermining the fundamental trust model of the operating environment.
This type of vulnerability is frequently associated with ATT&CK technique T1068: Exploitation for Privilege Escalation, where adversaries leverage software vulnerabilities to increase their access levels on compromised systems. The mitigation strategy primarily involves applying the provided security updates which introduce improved validation routines into the path handling subsystems. These patches likely enforce stricter checks on input strings, ensure canonicalization of paths before processing, and restrict operations based on strict allow-listing principles rather than permissive defaults. Administrators should prioritize deploying these updates across all managed macOS devices to close this attack vector immediately. Additionally, implementing defense-in-depth measures such as application sandboxing can limit the potential impact if a vulnerability is exploited by restricting the scope of file system access available to untrusted applications.