CVE-2026-43749 Overview
CVE-2026-43749 is a path traversal vulnerability [CWE-22] in Apple macOS caused by improper parsing of directory paths. A local application with limited privileges can exploit the flaw to gain root privileges on the affected system. Apple addressed the issue with improved path validation in macOS Sequoia 15.7.8, macOS Sonoma 14.8.8, and macOS Tahoe 26.6.
The vulnerability carries a CVSS score of 7.8 and affects confidentiality, integrity, and availability. Exploitation requires local access and low privileges, with no user interaction. No public proof-of-concept exploit is available, and the flaw is not listed in the CISA Known Exploited Vulnerabilities catalog.
Critical Impact
A malicious app can escalate to root on unpatched macOS systems, granting full control of the device.
Affected Products
- Apple macOS Sequoia (versions prior to 15.7.8)
- Apple macOS Sonoma (versions prior to 14.8.8)
- Apple macOS Tahoe (versions prior to 26.6)
Discovery Timeline
- 2026-07-27 - CVE-2026-43749 published to NVD
- 2026-07-28 - Last updated in NVD database
Technical Details for CVE-2026-43749
Vulnerability Analysis
CVE-2026-43749 is a directory path parsing flaw that maps to CWE-22 (Improper Limitation of a Pathname to a Restricted Directory). The affected macOS component fails to correctly validate directory paths before performing privileged operations. An application running with standard user privileges can craft input that the vulnerable code interprets as a permitted path.
Successful exploitation allows the attacker-controlled process to influence file operations executed by a higher-privileged component. The end result is elevation of privilege to root, which grants full read, write, and execute control over the operating system. Apple's advisories confirm the fix consists of stricter path validation logic in the affected parser.
The flaw requires local access, meaning an attacker must first execute code on the target system. This is a common post-initial-access primitive for malware that seeks persistence, System Integrity Protection tampering, or lateral movement across managed endpoints.
Root Cause
The underlying defect is improper canonicalization of directory paths. The vulnerable routine does not fully resolve path traversal sequences or symbolic components before applying access decisions. Attacker-supplied paths can therefore escape the intended directory scope and reference privileged locations.
Attack Vector
An attacker delivers a malicious application to a macOS user through phishing, a trojanized installer, or a supply-chain compromise. Once executed, the application invokes the vulnerable path-handling logic with a crafted directory argument. The privileged component operates on the attacker-controlled target, producing a root-level file write, execution, or configuration change.
No verified public exploit code exists for CVE-2026-43749. Apple's advisories for macOS Sequoia 15.7.8, Sonoma 14.8.8, and Tahoe 26.6 document the fix without releasing exploitation specifics.
Detection Methods for CVE-2026-43749
Indicators of Compromise
- Unsigned or newly installed applications spawning processes that write to /System, /Library/LaunchDaemons, or other root-owned directories.
- Unexpected setuid binaries or LaunchDaemon plists created shortly after execution of a user-installed application.
- Audit records showing user-level processes invoking privileged helpers with paths containing .. sequences or symbolic link redirection.
Detection Strategies
- Inventory macOS endpoints and flag hosts running versions prior to 15.7.8, 14.8.8, or 26.6 as exposed.
- Correlate process execution telemetry with subsequent privileged file writes to detect suspicious escalation chains.
- Alert on child processes of user applications that execute with effective UID 0 without a legitimate authorization prompt.
Monitoring Recommendations
- Collect Endpoint Security Framework (ESF) events for ES_EVENT_TYPE_NOTIFY_EXEC, ES_EVENT_TYPE_NOTIFY_RENAME, and ES_EVENT_TYPE_NOTIFY_LINK to observe path manipulation.
- Forward Unified Log entries related to privileged helpers and XPC services to a central analytics platform for retrospective hunting.
- Track installation events for applications outside the App Store and enforce Gatekeeper and notarization policies.
How to Mitigate CVE-2026-43749
Immediate Actions Required
- Update macOS endpoints to Sequoia 15.7.8, Sonoma 14.8.8, or Tahoe 26.6 through Software Update or your MDM platform.
- Restrict installation of unsigned or non-notarized applications on managed macOS fleets.
- Audit recently installed third-party applications and remove any that are unnecessary or untrusted.
Patch Information
Apple released fixes in macOS Sequoia 15.7.8, macOS Sonoma 14.8.8, and macOS Tahoe 26.6. Refer to Apple Support Document 128067, Apple Support Document 128071, and Apple Support Document 128072 for release notes and deployment guidance.
Workarounds
- No official workaround exists; apply the vendor patch as the primary remediation.
- Enforce least-privilege application deployment policies and disallow execution of unknown binaries via Gatekeeper.
- Segment high-value macOS endpoints and monitor for unexpected privilege transitions until patching is complete.
# Verify macOS version and trigger update via MDM or Software Update
sw_vers -productVersion
sudo softwareupdate --install --all --restart
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
