Microsoft August Update Caused Linux Boot Problem and Temporary Solution

TapTechNews August 24th news, Microsoft admitted that the cumulative update released on Patch Tuesday in August caused dual-boot devices of Windows and Linux unable to enter the Linux distribution normally, and the official has currently released a temporary solution.

Reason for the Problem

Microsoft released cumulative update KB5041585 on August 13th, and the version number of Windows 11 system users after installation rose to Build 22621.4037.

TapTechNews note: This problem mainly affects dual-boot devices of Windows and Linux, causing users to be unable to enter the Linux distribution normally, and will pop up the error of 'VerifyingshimSBATdatafailed'.

Microsoft officially stated that the problem is mainly because the detection mechanism fails to recognize certain systems, resulting in the update wrongly applying the advanced target setting of secure boot to the wrong system and damaging the Linux installation.

Temporary Solution

For users who have not deployed the August Windows update

Users run the following command to add the registry option.

reg add HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecureBoot\SBAT /v OptOut /d 1 /t REG_DWORD

For users who have already deployed the August Windows update

For users who have currently deployed and caused the Linux distribution to be unable to run, Microsoft provides a temporary solution:

1. Disable SecureBoot

2. Delete the SBAT update

Start Linux

Open the terminal and run the following command:

sudo mokutil --set-sbat-policy delete

If prompted, enter the root password.

Start Linux again.

3. Verify the revocation situation of SBAT

Run the following command in the terminal:

mokutil --list-sbat-revocations

4. Restart SecureBoot

5. Prevent the update of SBAT in Windows in the future:

Start into the Windows system

Open the Command Prompt as an administrator and run:

reg add HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecureBoot\SBAT /v OptOut /d 1 /t REG_DWORD

Related Reading:

Microsoft 'gets into trouble' and Linux takes the hit: After the Windows update patch, Linux can't open.