Apple releases emergency macOS updates to patch age-old security flaw in Screen Sharing

Apple has issued urgent updates for a wide range of Macs, including older Intel models, to fix a critical security flaw in Screen Sharing that could allow unauthenticated access. The patches cover macOS Tahoe, Sequoia, and Sonoma, elevating protection for systems still in use amidst a broader security overhaul.

Apple has released emergency macOS updates for a broad range of Macs, including older Intel models, after identifying a security flaw in Screen Sharing that could let someone on the same network get in without proper authentication. The patches cover macOS Tahoe 26.6.1, Sequoia 15.7.9 and Sonoma 14.8.9, with Apple saying the issue was fixed by improving internal authentication state management. The vulnerability is tracked as CVE-2026-65400 and was credited to researcher Alfredo Pesoli via Bynario Atlas.

The update is notable because it reaches machines that are now years old, extending protection to systems that many users may still rely on in business and home settings. Apple has said the flaw affected the Screen Sharing feature, and the company has not said it believes the problem was actively exploited before the fix was issued.

The release also fits a wider pattern of recent Apple security work. In late July, the company shipped large-scale updates across its platforms, including macOS Tahoe 26.6, and said those releases addressed a very large number of vulnerabilities. Security reports from the time described fixes ranging from kernel issues to sandbox escapes and other defects that could expose user data or weaken system protections.

Apple’s advice is straightforward: install the updates through System Settings, then General, then Software Update. For users who depend on Screen Sharing or other remote-access tools, the new releases are the safer option, particularly now that the flaw has been made public.