Kerberos encryption types must be configured to prevent the use of DES and RC4 encryption suites.

Certain encryption types are no longer considered secure. This setting configures a minimum encryption type for Kerberos, preventing the use of the DES and RC4 encryption suites.

If the following registry value does not exist or is not configured as specified, this is a finding:

Registry Hive: HKEY_LOCAL_MACHINE Registry Path: \SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\Kerberos\Parameters\

Value Name: SupportedEncryptionTypes

Value Type: REG_DWORD Value: 0x7ffffff8 (2147483640)

Configure the policy value for Computer Configuration >> Windows Settings >> Security Settings >> Local Policies >> Security Options >> "Network security: Configure encryption types allowed for Kerberos" to "Enabled" with only the following selected:

AES128_HMAC_SHA1 AES256_HMAC_SHA1 Future encryption types