I have an issue trying to do a kinit on ubuntu 22.04 with a user that has the "This account supports Kerberos AES 256 bit encryption" checkmark set.
I can kinit without issues to a user that does not have this checkmark set just fine, and weirdly enough, klist shows AES256 as encryption type even for this user:
~ % klist -e
Ticketzwischenspeicher: FILE:/...
Standard-Principal: user1@REALM...
Valid starting Expires Service principal
11.01.2023 12:13:58 11.01.2023 16:13:58 krbtgt/REALM@REALM
erneuern bis 11.01.2023 16:13:58, Etype (Skey, TKT): aes256-cts-hmac-sha1-96, aes256-cts-hmac-sha1-96
but once I set the checkmark on the user in AD to force AES265 bit encryption, the kinit fails with "KDC has no support for encryption type"
Also doesn't work manually with ktutil:
ktutil: addent -password -p user2@REALM -k 1 -e aes256-cts-hmac-sha1-96 -f
Passwort für user2@REALM:
addent: KDC has no support for encryption type beim Hinzufügen eines neuen Eintrags
I tried adding to /etc/krb5.conf the default encryptes:
[libdefaults]
default_realm = REALM
default_keytab_name = /etc/krb5.keytab
forwardable = true
proxiable = true
default_tkt_enctypes = aes256-cts aes128-cts des-cbc-md5 des-cbc-crc
default_tgs_enctypes = aes256-cts aes128-cts des-cbc-md5 des-cbc-crc
permitted_enctypes = aes256-cts aes128-cts des-cbc-md5 des-cbc-crc
but no change.
Setting the "Do not require Kerberos preauthentication" checkmark to the account doesn't change anything
Manually forcing AES256 on a user WITHOUT the checkmarks works fine as well:
ktutil: addent -password -p user1@REALM -k 1 -e aes256-cts-hmac-sha1-96 -f
Passwort für user1@REALM:
ktutil:
But as soon as I set the checkmark to that user, it's broken again.