CVE-2026-65342: Apple macOS Information Disclosure Flaw

CVE-2026-65342 Overview

CVE-2026-65342 is a permissions validation flaw in Apple macOS that allows an application to access sensitive user data. Apple addressed the issue with improved validation logic. The weakness is classified under [CWE-862] Missing Authorization, indicating that the affected component fails to properly enforce access controls before returning protected data to a requesting process. Apple resolved the vulnerability in macOS Golden Gate 27, macOS Sequoia 15.8, and macOS Tahoe 26.7.

Critical Impact
An app running on an unpatched macOS host can read sensitive user data without triggering the expected authorization checks, undermining privacy boundaries between applications.

Affected Products

Apple macOS versions prior to Golden Gate 27
Apple macOS versions prior to Sequoia 15.8
Apple macOS versions prior to Tahoe 26.7

Discovery Timeline

2026-09-14 - CVE-2026-65342 published to the National Vulnerability Database (NVD)
2026-09-17 - Last updated in NVD database

Technical Details for CVE-2026-65342

Vulnerability Analysis

The vulnerability stems from insufficient permission validation within a macOS component that handles user data. An application interacting with the affected interface can obtain data that should be gated behind an authorization check. Apple's advisory describes the fix as "a permissions issue was addressed with improved validation," indicating that the previous logic accepted requests without confirming that the caller held the required entitlement or user consent.

The issue is classified as [CWE-862] Missing Authorization. This class of flaw occurs when a component exposes a sensitive operation but does not verify that the requester is permitted to invoke it. On macOS, this typically bypasses Transparency, Consent, and Control (TCC) boundaries or entitlement checks that normally restrict access to user files, address book entries, calendar data, or other private stores.

Root Cause

The root cause is a missing or incomplete authorization check in a macOS system component. Apple's remediation adds validation to confirm that a calling process is entitled to the data it requests before returning results.

Attack Vector

Exploitation requires a malicious or compromised application running on the target macOS host. Once executed, the app invokes the affected interface and receives sensitive user data without prompting the user or failing the authorization check. Apple has not published exploitation details, and no public proof-of-concept exists at the time of writing. Refer to the Apple Support Article #149035, Apple Support Article #149042, and Apple Support Article #149043 for vendor-supplied technical context.

Detection Methods for CVE-2026-65342

Indicators of Compromise

No public indicators of compromise have been published by Apple or third-party researchers for CVE-2026-65342.
Unexpected access to protected user directories (~/Library, ~/Documents, address book, calendar) by non-approved applications may indicate exploitation attempts.

Detection Strategies

Monitor endpoint telemetry for applications reading TCC-protected resources without a corresponding user consent prompt.
Track process execution and file access patterns from newly installed or unsigned applications on macOS hosts.
Alert on applications enumerating user data stores shortly after first launch.

Monitoring Recommendations

Collect macOS Endpoint Security framework events for file access, process launches, and entitlement usage.
Centralize TCC database changes and access decisions for correlation across the fleet.
Validate that installed macOS builds match or exceed the patched versions listed by Apple.

How to Mitigate CVE-2026-65342

Immediate Actions Required

Update all macOS endpoints to Golden Gate 27, Sequoia 15.8, or Tahoe 26.7 as appropriate for the installed release train.
Inventory macOS hosts and prioritize patching for systems that process sensitive user data or handle regulated information.
Restrict installation of untrusted applications until patches are deployed.

Patch Information

Apple released fixes in macOS Golden Gate 27, macOS Sequoia 15.8, and macOS Tahoe 26.7. Patch details are documented in Apple Support Article #149035, Apple Support Article #149042, and Apple Support Article #149043.

Workarounds

No vendor-supplied workaround exists. Apply the official Apple update.
Limit installation of applications to those from the Mac App Store or trusted, notarized developers until patching is complete.
Review and tighten TCC permissions granted to third-party applications to minimize accessible user data.

bash

# Verify the installed macOS version meets the patched baseline
sw_vers -productVersion

# Trigger a software update check
sudo softwareupdate --list
sudo softwareupdate --install --all --restart