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

Documentable No

Rule ID SV-253460r971535_rule

CCI References

CCI-000803

Discussion

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.

Check Procedure

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)

Fix Action

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