From: Joseph Sutton <josephsutton@catalyst.net.nz>
Date: Mon, 21 Nov 2022 22:32:34 +0000 (+1300)
Subject: CVE-2022-37966 kdc: Assume trust objects support AES by default
X-Git-Tag: samba-4.16.8~32
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=c13c60ffbf7f86011594268cc48a1f9f1991f664;p=thirdparty%2Fsamba.git

CVE-2022-37966 kdc: Assume trust objects support AES by default

As part of matching the behaviour of Windows, assume that trust objects
support AES256, but not RC4, if not specified otherwise.

BUG: https://bugzilla.samba.org/show_bug.cgi?id=15219
BUG: https://bugzilla.samba.org/show_bug.cgi?id=15237

Signed-off-by: Joseph Sutton <josephsutton@catalyst.net.nz>
Reviewed-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Andrew Bartlett <abartlet@samba.org>
(cherry picked from commit 4bb50c868c8ed14372cb7d27e53cdaba265fc33d)
---

diff --git a/source4/kdc/db-glue.c b/source4/kdc/db-glue.c
index ccf3951463b..8becada4457 100644
--- a/source4/kdc/db-glue.c
+++ b/source4/kdc/db-glue.c
@@ -1472,9 +1472,10 @@ static krb5_error_code samba_kdc_trust_message2entry(krb5_context context,
 	NTSTATUS status;
 
 	if (dsdb_functional_level(kdc_db_ctx->samdb) >= DS_DOMAIN_FUNCTION_2008) {
+		/* If not told otherwise, Windows now assumes that trusts support AES. */
 		supported_enctypes = ldb_msg_find_attr_as_uint(msg,
 					"msDS-SupportedEncryptionTypes",
-					supported_enctypes);
+					ENC_HMAC_SHA1_96_AES256);
 	}
 
 	status = dsdb_trust_parse_tdo_info(mem_ctx, msg, &tdo);