Check Point Endpoint Incident: macOS 26.3 Compatibility Issue

Final Update: macOS Tahoe 26.3 Compatibility Issue
We have completed our investigation into the macOS Tahoe 26.3 compatibility issue affecting a limited subset of devices running Harmony Endpoint Threat Prevention blades.

The root cause has been identified, and recovery and mitigation steps are now available.

Customers who upgraded to macOS Tahoe 26.3 and are experiencing boot issues should follow the guidance in SecureKnowledge article SK184676:
https://supportcenter.checkpoint.com/supportcenter/portal?solutionid=sk184676

Devices that have not yet upgraded to macOS Tahoe 26.3 should wait for a forthcoming Harmony Endpoint update before proceeding with the OS upgrade.

Our engineering teams are preparing an updated client version to fully address the compatibility change introduced in macOS Tahoe 26.3.

This incident is now considered mitigated. For additional assistance, please contact Check Point Support and reference SK184676.

We are currently investigating an issue impacting macOS devices that were upgraded to Apple macOS version 26.3.
Following the OS update, some devices running Harmony Endpoint may experience a reboot loop and are unable to complete the startup process.

Current Status
Our engineering teams have identified the trigger and are actively working on mitigation steps and a permanent fix.

Impact
This issue affects macOS devices that upgraded to macOS Tahoe 26.3 while Harmony Endpoint Threat Prevention blades were installed, specifically:
-Forensics
-Threat Emulation
-Threat Hunting
-Anti Ransomware
Devices without these blades enabled are not impacted.

Recommended Action
We recommend that customers temporarily pause upgrades to macOS 26.3 until further notice.
For devices that are already impacted, recovery instructions are available in SecureKnowledge article SK184676:
https://supportcenter.checkpoint.com/supportcenter/portal?solutionid=sk184676

If you require assistance, please contact Check Point Support and reference this incident.
We will provide another update as additional information becomes available.