Overview
- Apple released macOS Tahoe 26.5.1 on June 1, 2026 to fix an issue that could cause some M5 Macs to shut down unexpectedly when certain content‑filtering network extensions are active.
- Content‑filtering network extensions are tools used by enterprises and schools to monitor or block web traffic on managed Macs and the bug arose from how those extensions interact with M5 hardware.
- Apple’s release notes say the update is a reliability patch with no new user features and the company did not disclose how many Macs were affected.
- Organizations should install 26.5.1 via System Settings → Software Update, test the update against their filtering vendors, and schedule any required reboots to reduce support disruption.
- The patch follows macOS Tahoe 26.5 three weeks earlier, which fixed black‑screen and SMB restart problems, and it continues Apple’s short‑term run of enterprise stability fixes ahead of WWDC and macOS 27.