CVE-2026-43771: Apple macOS stack overflow denial of service

Executive brief

A vulnerability in macOS could allow a malicious application to cause a system crash or denial-of-service. This affects the core operating system used on Apple laptops and desktops. Users should update to the latest versions of macOS Sequoia, Sonoma, or Tahoe to resolve the issue.

Technical details

A stack overflow vulnerability exists in macOS due to insufficient input validation. A locally installed malicious application can exploit this flaw to trigger a denial-of-service (DoS) condition, potentially crashing the system or specific services. Apple has addressed the issue by improving input validation mechanisms. The vulnerability is fixed in macOS Sequoia 15.7.8, macOS Sonoma 14.8.8, and macOS Tahoe 26.6.

Affected products

• Apple macOS Sequoia before 15.7.8
• Apple macOS Sonoma before 14.8.8
• Apple macOS Tahoe before 26.6

Timeline

• 2026-07-27: advisory
• 2026-07-27: patched

References

• https://support.apple.com/en-us/128067
• https://support.apple.com/en-us/128071
• https://support.apple.com/en-us/128072