Microsoft Windows Server 2022

Windows Server 2022 Kerberos encryption types must be configured to prevent the use of DES and RC4 encryption suites

STIG ID: WN22-SO-000290 | SRG: SRG-OS-000120-GPOS-00061 | Severity: Medium | CCI: CCI-000803 | Vulnerability ID: V-254473

Description

Certain encryption types are no longer considered secure. The DES and RC4 encryption suites must not be used for Kerberos encryption.Note: Organizations with domain controllers running earlier versions of Windows where RC4 encryption is enabled, selecting "The other domain supports Kerberos AES Encryption" on domain trusts, may be required to allow client communication across the trust relationship.

Check

C-57958r849233_chk

If the following registry value does not exist or is not configured as specified, this is a finding:Registry Hive: HKEY_LOCAL_MACHINERegistry Path: \SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\Kerberos\Parameters\Value Name: SupportedEncryptionTypesValue Type: REG_DWORDValue: 0x7ffffff8 (2147483640)

Fix

F-57909r849234_fix

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_SHA1AES256_HMAC_SHA1Future encryption typesNote: Organizations with domain controllers running earlier versions of Windows where RC4 encryption is enabled, selecting "The other domain supports Kerberos AES Encryption" on domain trusts, may be required to allow client communication across the trust relationship.