BitLocker recovery after BIOS reset wiped Secure Boot 2023 certs – no key, need help restoring db to match PCR7


lisjyngvlngsfdv

New member
Local time
1:10 AM
Posts
1
OS
Windows 11
Hi all. Hoping someone experienced with the Secure Boot 2023 certificate rollout can help.

System info:
Laptop: MSI Katana GF76 12UD (MS-17L4), BIOS E17L4IMS.10E (06/2022, never updated)
CPU: Intel Core i5-12500H, TPM = Intel PTT
RAM: 24 GB DDR4, GPU: RTX 3050 Ti Laptop, 512 GB NVMe SSD
Windows 11, fully updated (exact build unknown – the PC can’t boot)

Timeline:

  • BitLocker (device encryption) was enabled automatically. TPM-only protector, sealed 2026-09-24 (shown on the recovery screen) – most likely right after Windows applied the Windows UEFI CA 2023 db update.
  • Yesterday the BIOS settings reset (date went to 04/01/2024, likely CMOS). Secure Boot keys returned to factory defaults (Factory Default Key Provisioning: Enabled).
  • Boot went to BitLocker recovery: error 7_3_80000001_80000001_db_db_7_7_19c4…13eb_2d64…f21c. So PCR7 event #3 (db) mismatches, PK and KEK match. Expected db digest 19c4…13eb, observed 2d64…f21c.
  • With Secure Boot enabled, the boot manager now fails (“Secure Boot Violation: Invalid signature”) because it’s signed by Windows UEFI CA 2023, which the factory db lacks. Secure Boot is currently disabled (now error E_FVE_SECURE_BOOT_DISABLED, PCR7 event 0).
We don’t have the recovery key. TPM has NOT been cleared, the drive is untouched. We have a Mac and can make an Ubuntu live USB to run any commands needed.

Plan: re-append to db exactly what Windows added (signed payloads from microsoft/secureboot_objects), so db hashes to 19c4…13eb, then re-enable Secure Boot and let TPM unseal.

Questions:

  1. Which db payloads does Windows apply, and in what order (Windows UEFI CA 2023 only, or also Microsoft UEFI CA 2023 / Option ROM CA 2023)? Would dbx have been updated too before 24.09?
  2. Best way to append them on an MSI/AMI board: Ubuntu live USB with efi-updatevar -a, or something else?
  3. Can we pre-compute the db event digest offline (from the factory db dump + candidate ESLs) to verify against 19c4…13eb before writing?
Any help hugely appreciated – critical documents on the drive.
 
Windows Build/Version
Windows 11, fully updated (24H2/25H2, exact build unknown – PC can’t boot)

My Computer My Computer

At a glance

Windows 11
OS
Windows 11
Computer type
Laptop
Manufacturer/Model
MSI Katana GF76 12UD
This one sounds tricky. While you could use Linux and mess around with EFI tools, I would try this:

1. Enter the UEFI's Secure Boot menu, get a list of the current KEK and DB keys. I know you said the KEK matches, but just visually re-confirm.

2. If you're certain that before the BIOS glitch, everything was properly updated then you can re-add the missing certs through the Secure Boot menu's manual key enrollment menu. CA 2023 update adds:
- Windows UEFI CA 2023​
- Microsoft UEFI CA 2023​
- Option ROM 2023​

3. All three certs are available as DER cert files, which the MSI should be able to import if you copy them to a FAT32-formatted USB drive. Download a copy of those certs from the MS Secure Boot Objects GitHub:
secureboot_objects/PreSignedObjects/DB/Certificates at main · microsoft/secureboot_objects

4. Sometimes your UEFI will require you to rename the file extension as .cer or .crt, if its doesn't accept .der.

5. In the worse case of the final DB hash doesn't match, return to Secure Boot menu and delete the added keys.
 

My Computer My Computer

At a glance

Windows 7
OS
Windows 7

My Computers My Computers

  • At a glance

    Windows 11 HomeRyzen 7 5825u64GB DDR4 3200Ryzen 7 5825u
    OS
    Windows 11 Home
    Computer type
    PC/Desktop
    Manufacturer/Model
    HP 24" AiO
    CPU
    Ryzen 7 5825u
    Motherboard
    HP
    Memory
    64GB DDR4 3200
    Graphics Card(s)
    Ryzen 7 5825u
    Sound Card
    Realtek External 5w speaker bar.
    Monitor(s) Displays
    24" HP AiO
    Screen Resolution
    1920 x 1080 @60 Hz
    Hard Drives
    1TB WD Blue SN580 M2 SSD Partitioned C:/D: drives.
    2x 1TB USB HDD External Backup/Storage.
    all VeraCrypt encrypted.
    PSU
    90W external power brick
    Case
    24" All in One
    Cooling
    Default Air Cooling
    Keyboard
    Dell WiFi UK extended
    Mouse
    Dell WiFi 3 Button
    Internet Speed
    1GB full fibre
    Browser
    Vivaldi Browser/Email/Calendar
    Antivirus
    AVG Internet Security/Windows Defender
    Other Info
    Mainly Open Source Software
  • At a glance

    Ubuntu 22.04.5 LTSi5 7200u16GB DDR4Intel
    Operating System
    Ubuntu 22.04.5 LTS
    Computer type
    Laptop
    Manufacturer/Model
    Dell 13" Latitude 2017
    CPU
    i5 7200u
    Motherboard
    Dell
    Memory
    16GB DDR4
    Graphics card(s)
    Intel
    Sound Card
    Intel
    Monitor(s) Displays
    13" Dell Laptop
    Hard Drives
    250GB Crucial 2.5" SSD
    Mouse
    Generic WiFi 3 button
    Internet Speed
    WiFi only
    Browser
    Firefox
    Antivirus
    ClamAV TK
    Other Info
    Mainly Open Source Software
Back
Top Bottom