How are the compatibility settings for certificate templates technically mapped?

Since the Certificate Services management tools in Windows Server 2012, you can select the desired compatibility for the certificate authority and certificate recipient when configuring a certificate template.

In the following, this function is described in more detail, as well as possible effects in practice.

For an overview of which options become available when changing each compatibility setting, see the article "Overview of the availability of options when changing the compatibility settings of a certificate template„.

The compatibility settings are available as a bitmask in the attribute msPKI private key flag mapped in the certificate template.

The msPKI private key flag two subordinate attributes:

  • CTPRIVATEKEY_FLAG_SERVERVERSION_SHIFT
  • CTPRIVATEKEY_FLAG_CLIENTVERSION_SHIFT

Possible values for CTPRIVATEKEY_FLAG_SERVERVERSION_SHIFT

Operating systemFlagValue
Default settingTEMPLATE_SERVER_VER_NONE0
Windows Server 2003TEMPLATE_SERVER_VER_200310000 (65536)
Windows Server 2008TEMPLATE_SERVER_VER_200820000 (131072)
Windows Server 2008 R2TEMPLATE_SERVER_VER_2008R230000 (196608)
Windows Server 2012TEMPLATE_SERVER_VER_WIN840000 (262144)
Windows Server 2012 R2TEMPLATE_SERVER_VER_WINBLUE50000 (327680)
Windows Server 2016TEMPLATE_SERVER_VER_THRESHOLD60000 (393216)

Possible values for CTPRIVATEKEY_FLAG_CLIENTVERSION_SHIFT

Operating systemFlagValue
Default settingEMPLATE_CLIENT_VER_NONE0
Windows XPTEMPLATE_CLIENT_VER_XP1000000 (16777216)
Windows VistaTEMPLATE_CLIENT_VER_VISTA2000000 (33554432)
Windows 7TEMPLATE_CLIENT_VER_WIN73000000 (50331648)
Windows 8TEMPLATE_CLIENT_VER_WIN84000000 (67108864)
Windows 8.1TEMPLATE_CLIENT_VER_WINBLUE5000000 (83886080)
Windows 10TEMPLATE_CLIENT_VER_THRESHOLD6000000 (100663296)

Query the attribute for a certificate template

Do you know TameMyCerts? TameMyCerts is an add-on for the Microsoft certification authority (Active Directory Certificate Services). It extends the function of the certification authority and enables the Application of regulationsto realize the secure automation of certificate issuance. TameMyCerts is unique in the Microsoft ecosystem, has already proven itself in countless companies around the world and is available under a free license. It can downloaded via GitHub and can be used free of charge. Professional maintenance is also offered.

The following command line command can be used to query the values currently configured for a certificate template for the two flags:

certutil -v -template {name-of-template} | findstr VERSION_SHIFT

The template name corresponds to the Active Directory object name, not the display name.

Alternatively, it is also possible to use the msPKI private key flag directly on the pKICertificateTemplate object in the Active Directory.

certutil -v -ds "{DN-of-template-object}"

Example:

certutil -v -ds "CN=ADCSLaboratoryUser,CN=Certificate Templates,CN=Public Key Services,CN=Services,CN=Configuration,DC=intra,DC=adcslabor,DC=de"

If you check directly after a change to the certificate template, you should refresh the client-side cache with certutil -pulse to get the latest information.

Related links:

en_USEnglish