en-US/about_PrintNightmareMitigations.help.txt

TOPIC
    about_PrintNightmareMitigations
 
SHORT DESCRIPTION
    Tests or applies PrintNightmare mitigations.
 
LONG DESCRIPTION
    This PowerShell module will test or apply PrintNightmare mitigations to the
    current computer.
 
Required Updates
    In order for these mitigations to be effective, your computer must have one
    of the following updates, or any later cumulative update:
 
    - Windows 10 (2004+): KB5004945
    - Windows 10 (1909): KB5004946
    - Windows 10 (1809): KB5004947
    - Windows 10 (1607): KB5004948
    - Windows 10 (1507): KB5004950
    - Windows 8.1: KB5004954 (rollup) or KB5004958 (security-only)
    - Windows 7: KB5004953 (rollup) or KB5004951 (security-only)*
 
    - Windows Server 2019: KB5004947
    - Windows Server 2016: KB5004948
    - Windows Server 2012 R2: KB5004954 (rollup) or KB5004958 (security-only)
    - Windows Server 2012: KB5004956 (rollup) or KB5004960 (security-only)
    - Windows Server 2008 R2: KB5004953 (rollup) or KB5004951 (security-only)*
    - Windows Server 2008: KB5004955 (rollup) or KB5004959 (security-only)*
     
    *Note that updates for Windows 7 and the Windows Server 2008 family require
    a valid ESU license.
 
 
EXAMPLES
 
Checking Mitigations
    PS C:\> Test-PrintNightmareMitigation
 
    This example will determine whether or not the system is hardened to resist
    PrintNightmare by checking the existence and values of the two required and
    one optional registry values.
 
Applying Required Mitigations
    PS C:\> Set-PrintNightmareMitigation
 
    This example will harden this system against PrintNightmare by setting both
    of the required registry entries. However, non-administrators may continue
    to install printer drivers.
 
Applying All Mitigations
    PS C:\> Set-PrintNightmareMitigation -RestrictDriverInstallationToAdministrators
 
    This example will harden this system against PrintNightmare by setting both
    of the required registry entries. In addition, non-administrators will now
    be blocked from installing printer drivers.
 
 
NOTE
    As it writes to the registry, the cmdlet Set-PrintNightmareMitigation must
    be run as an administrator.
 
 
TROUBLESHOOTING NOTES
 
Expected Outcome
    Changing these registry values will result in a User Account Control prompt
    when adding, changing, or receiving an update for Point and Print settings.
    In addition, if you restrict printer driver installation to non-admins, the
    obvious will happen.
 
Goodbye, SQL Server 2005
    On Windows 7, Windows Server 2008, and Windows Server 2008 R2, installing a
    required update -- or a later update -- may cause connections to SQL Server
    2005 to fail with error 40. This is because of security hardening changes
    introduced in this update, and is not related to any registry changes which
    you or this module might make to your system. Microsoft's resolution is to
    upgrade to a supported version of SQL Server. (Sorry.)
 
ESU Required for Out-of-Support Platforms
    The PrintNightmare patches for Windows 7, Windows Server 2008, and related
    operating systems require a valid Extended Servicing Updates subscription.
    If you have not installed a license key for ESU, this update will fail to
    install.
 
SEE ALSO
    Test-PrintNightmareMitigation
    Set-PrintNightmareMitigation
    https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2021-34527
 
KEYWORDS
    PrintNightmare CVE-2021-34527 Print Spooler spoolsv.exe