cbcvebase.
CVE-2024-20666
published 2024-01-09

CVE-2024-20666: BitLocker Security Feature Bypass Vulnerability BitLocker Security Feature Bypass Vulnerability

medium6.6CVSS 3.1
AVPACLPRLUINSUCHIHAH
ITWVulnCheck KEV
Exploited in the wild
EPSS
3.10%
86.1th percentile
BitLocker Security Feature Bypass Vulnerability BitLocker Security Feature Bypass Vulnerability

Affected

27 ranges· showing 25
VendorProductVersion rangeFixed in
microsoftwindows_10_version_1507>= 10.0.10240.0 < 10.0.10240.2040210.0.10240.20402
microsoftwindows_10_version_1607>= 10.0.14393.0 < 10.0.14393.661410.0.14393.6614
microsoftwindows_10_version_1809>= 10.0.0 < 10.0.17763.532910.0.17763.5329
microsoftwindows_10_version_1809>= 10.0.17763.0 < 10.0.17763.532910.0.17763.5329
microsoftwindows_10_version_21h2>= 10.0.19043.0 < 10.0.19044.393010.0.19044.3930
microsoftwindows_10_version_22h2>= 10.0.19045.0 < 10.0.19045.393010.0.19045.3930
microsoftwindows_11_version_21h2>= 10.0.0 < 10.0.22000.271310.0.22000.2713
microsoftwindows_11_version_22h2>= 10.0.22621.0 < 10.0.22621.300710.0.22621.3007
microsoftwindows_11_version_22h3>= 10.0.22631.0 < 10.0.22631.300710.0.22631.3007
microsoftwindows_11_version_23h2>= 10.0.22631.0 < 10.0.22631.300710.0.22631.3007
microsoftwindows_server_2016>= 10.0.14393.0 < 10.0.14393.661410.0.14393.6614
microsoftwindows_server_2019>= 10.0.17763.0 < 10.0.17763.532910.0.17763.5329
microsoftwindows_server_2022>= 10.0.20348.0 < 10.0.20348.222710.0.20348.2227
msrcwindows_10
msrcwindows_10_version_1607
msrcwindows_10_version_1809
msrcwindows_10_version_21h2
msrcwindows_10_version_22h2
msrcwindows_11_version_21h2
msrcwindows_11_version_22h2
msrcwindows_11_version_23h2
msrcwindows_11_version_24h2
msrcwindows_server_2012_r2
msrcwindows_server_2016
msrcwindows_server_2019

Detection & IOCsextracted from sources · hover to see the quote

  • CVE-2024-20666 is a BitLocker encryption bypass vulnerability requiring physical access to the device; threat model should prioritize physical access scenarios to encrypted systems
  • Patch status indicator: systems still showing 0x80070643 error after KB5034441 install attempt have NOT been patched for CVE-2024-20666 and remain vulnerable to BitLocker bypass
  • ·The patch (KB5034441) silently fails with error 0x80070643 on systems where the WinRE partition is too small (~500 MB default); systems may appear to have attempted patching but remain unpatched — verify actual WinRE update status independently
  • ·Even a brand-new Windows 10 install with the latest ISO creates a WinRE partition (~522 MB) that is too small for KB5034441, meaning a large portion of the Windows 10 fleet is silently unpatched
  • ·Microsoft confirmed no automated fix will be released; manual WinRE partition resize of 250 MB is required — compliance/patch management tools may incorrectly report these systems as patched
  • ·The PowerShell remediation script patches WinRE directly without installing KB5034441; after running it, Windows Update will still repeatedly attempt to install KB5034441 and show errors unless the update is hidden via Microsoft's Show or Hide Tool

CVSS provenance

nvdv3.16.6MEDIUMCVSS:3.1/AV:P/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
cvelistv56.6MEDIUM
vulncheck6.6MEDIUM
vendor_msrc7.3HIGH
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