Microsoft Blocks Security Updates Due to Windows 11 24H2 Bug

• A critical bug affected the Windows 11 24H2 update, which has been recently released, so Microsoft decided to block security updates for now.
• The vulnerability impacts devices updated via CDs or USB flash drives, preventing the systems from getting further updates.
• Windows Update or the Microsoft Update Catalog updates are not prone to this security issue.

Microsoft has issued an alert regarding a critical bug impacting the recently released Windows 11 24H2 update. The flaw, identified on December 24, 2024, affects devices updated using physical media, such as CDs or USB flash drives, leaving systems unable to receive further security updates and exposing them to potential cyber threats.

The issue arises when users install Windows 11 24H2 using physical installation media that includes security updates released between October 8 and November 12, 2024. During installation, the affected devices fail to properly configure for subsequent updates, effectively blocking the system from receiving additional security patches.

Microsoft has clarified that users updating their systems via Windows Update or the Microsoft Update Catalog are not prone to this bug. However, it poses significant risks for businesses, educational institutions, and technical professionals who often rely on physical media for large-scale deployments or clean system installations.

Recognizing the severity of the situation, Microsoft has prioritized resolving the issue. While a permanent fix is under development, the company has recommended the following immediate actions to mitigate risks:

• Avoid using affected media – Refrain from installing Windows 11 24H2 using installation media that includes security updates from October or November 2024.
• Create updated installation media – Users are advised to generate new installation media incorporating the monthly security update released on December 10, 2024, or later.
• Reinstall affected systems – For systems already impacted, Microsoft recommends a full reinstallation using the updated media to restore the device's ability to receive future security updates.

For IT administrators and individual users, verifying the installation date and source is crucial if Windows 11 was installed using physical media recently. Systems installed using media from the affected period should apply the December 2024 security update either via Windows Update or the Microsoft Update Catalog to resolve the issue.