Microsoft Slams Shut Critical BitLocker Flaw with Urgent Patch

Microsoft has issued an urgent patch for a critical flaw in Windows BitLocker that could allow authorized attackers to execute code on affected machines.

The vulnerability, CVE-2026-69449, is a heap-based buffer overflow in the Windows BitLocker component and affects every supported Windows client and server release from 2012 through 2025.

Microsoft patched the issue on September 8, 2026, but warns that the fix may not be enough to prevent exploitation, especially for systems handling sensitive encrypted data.

Administrators are advised to prioritize deployment of the patch, particularly for Server 2012 and 2012 R2 fleets with operational dependencies that slow patching.