Windows users who have installed a new KB5012170 security update for Secure Boot have encountered various issues, ranging from boots failing with BitLocker Recovery prompts to performance issues.
A UEFI bootloader loads immediately after a device is started and is responsible for launching the UEFI environment with the Secure Boot feature to allow only trusted code to be executed when starting the Windows booting process.
During the August 2022 Patch Tuesday, Microsoft released the standalone KB5012170 'Security update for Secure Boot DBX' to resolve vulnerabilities found in various UEFI bootloaders that threat actors could use to bypass the Windows Secure Boot feature and execute unsigned code.
To fix these vulnerabilities, Microsoft added the certificates required to load the vulnerable UEFI bootloaders to the UEFI Revocation List - the Secure Boot Forbidden Signature Database (DBX), thus preventing them from being used with Secure Boot.
However, if your device does not have a valid bootloader, attempting to install the KB5012170 update will generate an 0x800f0922 error and prevent the installation from completing, which is a good thing as your device would no longer boot otherwise.
Microsoft says you can fix this error by checking for updated UEFI firmware from your device manufacturer.
KB5012170 causing numerous issues
In addition to the 0x800f0922 error, Windows users are now reporting problems with Windows after installing the KB5012170 update.
As first reported by TheRegister, some Windows users are encountering BitLocker Recovery screens after installing the update. According to one of their readers, 2% of the Windows 11 devices showed BitLocker recovery screens after installing the update.
Other users on the Microsoft Answers forum, Twitter, and Reddit have also said they are experiencing the same behavior.
For those affected by the Bitlocker recovery screen, you can typically find your recovery key stored in your Microsoft Account. Instructions on how to find this information can be found in this Microsoft support document.
For enterprise users, Windows admins can retrieve the Bitlocker recovery key from the Active Directory Users and Computers.
In addition to the BitLocker recovery problems, BleepingComputer readers have said they are encountering slow boot times, or their disk configurations changed from RAID to AHCI in the firmware settings.
"I have Windows 10 21H1 and after I downloaded the update last week I noticed the boot time change to VERY long," reads a comment on BleepingComputer.
"Can confirm that. Whats worse, the update changed my RAID mode to AHCI, so I had to manually put that back on approx 10 devices, that ran into BSOD. All of them. Almost brand new Latitudes 5320 and all behaved the same. You can see, if the update changed your RAID mode too," reads another comment.
Thankfully, users should only run into these issues once, and they should go away after you enter the BitLocker recovery key or modify disk configurations.
However, it is strongly advised that you check for updated UEFI firmware before attempting to install this update to save yourself a potential headache.
Comments
NoneRain - 1 year ago
OEM firmware issue… The thing is, Bitlocker comes active in many OEM, but they never clarify this to the user. They also don't release the necessary firmware updates in time, and certainly don't submit 'em to MSU.
Hmm888 - 1 year ago
Consumer websites such as this and media need to pressure OEMs to let their customers know the risk and media should call them out when they don't. But I digress, that's only being foolishly optimistic.
Richard_Cranium - 1 year ago
I'm in IT and this has been a bug on windows 10 as well. It's been somewhat rare as it has only happen 3 times out of about 150+ computers but those 3 times have been a nightmare. Dell told me that bitlocker won't activate itself so seeing this gives some validation to my claims.
NoneRain - 1 year ago
First thing I do with new devices is to get rid of the OEM system.
Delete all partition and install fresh OS. This resolves a lot of issues related to the shady bloatware, and I think the Bitlocker “activating itself” could also be avoided this way.
TairikuOkami - 1 year ago
Bitlocker activates itself on 11, when requirements are met. It supposedly asks the user to backup the key, but since the user does not even know, what Bitlocker is, he usually ignores it. I make sure to disable Bitlocker/EFS, before it has a chance to rain hell on PC. It is basically ransomware.
reg add "HKLM\System\CurrentControlSet\Control\BitLocker" /v "PreventDeviceEncryption" /t REG_DWORD /d "1" /f
fsutil behavior set disableencryption 1
cipher /d /s:C:\
sc config BDESVC start= disabled
sc config EFS start= disabled
CapMReynolds - 1 year ago
I am curious, how many computers with Windows 10 Home has this affected? On a forum that I moderate we have had a couple of users that had an update and subsequent BitLocker screen, but the Home version does not have BitLocker enabled or even an option so this shouldn't be happening.
noelprg4 - 1 year ago
about none of them using Win10 Home, CapMReynolds
cuz my father's Toshiba Satellite 2013 laptop had received the KB5012170 update for 64bit Win10 Home 21H2 in mid-August and installed automatically without my knowledge (and it has UEFI with secure boot enabled but no TPM) and the Toshiba laptop is working fine after KB5012170 was installed.
maybe for those using either Windows 10 Pro or Windows 11 Pro (or even Windows 11 Home) might be another story
Yawera - 1 year ago
Does anyone has a solution on this ?
I’ve been locked out of my PC for the last 4 days. Have tried 18 different methods, including bootable drive with Ubuntu on it and the SSD Still shows locked. No way to access it
bubbagump72 - 1 year ago
We have discovered that the BitLocker prompt can be bypassed by pressing Ctrl+Alt+Del
This works on Dell Latitude 7470 and we had this behavior in the past. A recent BIOS update fixed it, but it is back after the KB5012170.
noelprg4 - 1 year ago
hi Lawrence.
KB5012170 is also available for the Windows 11 2022 (22H2) Update, which is being pushed to those systems by MS, as noted by this recent Neowin article:
https://www.neowin.net/news/microsoft-pushes-windows-11-22h2-secure-boot-dbx-update-thats-known-to-be-bug-ridden/