CVE-2026-28933: Apple macOS Use-After-Free Vulnerability

CVE-2026-28933 Overview

CVE-2026-28933 is a use-after-free vulnerability [CWE-416] affecting multiple versions of Apple macOS. A local application can trigger the flaw to cause unexpected system termination, resulting in a denial-of-service condition. Apple addressed the issue with improved memory management in macOS Sequoia 15.7.8, macOS Sonoma 14.8.8, and macOS Tahoe 26.6.

The vulnerability requires local access and low privileges, with no user interaction needed. Impact is limited to availability, with no confidentiality or integrity consequences reported by Apple.

Critical Impact
A local application can exploit a memory management flaw in macOS to trigger unexpected system termination, disrupting availability for the affected host.

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

2026-09-14 - CVE-2026-28933 published to NVD
2026-09-15 - Last updated in NVD database

Technical Details for CVE-2026-28933

Vulnerability Analysis

The flaw is a use-after-free condition [CWE-416] in an unspecified macOS component. Use-after-free bugs occur when a program continues to reference memory after it has been released. An attacker with local access can craft an application that triggers this dangling reference, corrupting internal kernel or system-service state.

Apple describes the outcome as unexpected system termination, which maps to a denial-of-service impact. The advisory does not indicate that the flaw is usable for code execution, privilege escalation, or information disclosure.

Root Cause

The root cause is improper memory lifecycle management. A code path releases a memory object while other references remain valid, and a subsequent operation dereferences the freed object. Apple's fix, per the advisory, applies improved memory management to close the window where the stale reference can be reached.

Attack Vector

Exploitation requires local execution on the target macOS host with low privileges. No user interaction is required. A malicious or compromised application on the system invokes the vulnerable code path to trigger the use-after-free and force the system to terminate. No public proof-of-concept or in-the-wild exploitation has been reported, and the vulnerability is not listed in the CISA Known Exploited Vulnerabilities catalog.

No verified exploitation code is available. See Apple's advisories for further technical detail: Apple Support Document #128067, Apple Support Document #128071, and Apple Support Document #128072.

Detection Methods for CVE-2026-28933

Indicators of Compromise

Unexpected kernel panics or abrupt system reboots on macOS endpoints running versions prior to 15.7.8, 14.8.8, or 26.6.
Panic logs under /Library/Logs/DiagnosticReports/ correlating with execution of an untrusted or newly installed application.
Repeated system terminations tied to a single process or bundle identifier.

Detection Strategies

Inventory macOS build versions across the fleet and flag hosts below the patched builds.
Correlate application launch telemetry with subsequent panic or reboot events to identify suspect binaries.
Monitor for unsigned or newly delivered applications immediately preceding system termination events.

Monitoring Recommendations

Forward macOS DiagnosticReports and unified log panic entries to a central SIEM for review.
Alert on clusters of unexpected reboots across multiple endpoints, which may indicate a common malicious binary.
Track process execution and code signing status to identify low-reputation applications on unpatched hosts.

How to Mitigate CVE-2026-28933

Immediate Actions Required

Update affected systems to macOS Sequoia 15.7.8, macOS Sonoma 14.8.8, or macOS Tahoe 26.6.
Prioritize patching on multi-user systems, developer workstations, and shared macOS infrastructure where local access is broader.
Restrict installation of untrusted applications until patches are applied.

Patch Information

Apple resolved CVE-2026-28933 by applying improved memory management. Patched builds are documented in Apple Support Document #128067, Apple Support Document #128071, and Apple Support Document #128072. Administrators should deploy the corresponding update for each macOS release train in their environment.

Workarounds

No vendor-supplied workaround is available; apply the security update.
Enforce Gatekeeper and notarization requirements to limit execution of untrusted applications.
Apply least-privilege policies and restrict local account rights on shared macOS endpoints.

bash

# Verify the installed macOS version against patched builds
sw_vers -productVersion

# Trigger a check for available Apple software updates
sudo softwareupdate --list

# Install all available Apple software updates and restart if required
sudo softwareupdate --install --all --restart