Microsoft has confirmed a known issue causing performance problems, boot issues, and freezes on Windows Server 2019 systems after installing the August 2024 security updates. The company acknowledged widespread reports from Windows admins experiencing server slowdowns, unresponsiveness, and high CPU usage with Cryptographic Services.
The issue affects a limited number of organizations when running Antivirus software that scans the ‘% systemroot%\system32\catroot2’ folder for Windows updates due to an error in catalog enumeration. Affected admins have linked the problem to the Antimalware Service Executable service and Windows Defender background process.
Impacted IT environments may experience increased CPU utilization, disk latency, disk utilization, degraded OS or application performance, Cryptographic Services failure, slow boot, freezes, or a black screen. Home or Pro Windows editions are less likely to be affected due to this issue being more common in enterprise environments.
Microsoft has resolved the widespread known issue through Known Issue Rollback (KIR) and is working to include the fix in a future Windows update. To resolve the issue on impacted devices, admins must install and set up the KB5041578 240816_21501 KIR Group Policy. The company will not require additional configuration once the resolution update is released.
Microsoft has also confirmed that the August 2024 Windows security updates are breaking Linux booting on dual-boot systems with Secure Boot enabled.
Source: https://www.bleepingcomputer.com/news/microsoft/microsoft-august-updates-cause-windows-server-boot-issues-freezes/