From: Andreas Schneider Date: Mon, 9 Aug 2021 15:20:31 +0000 (+0200) Subject: CVE-2020-25719 s4:kdc: Check if the pac is valid before updating it X-Git-Tag: samba-4.13.14~58 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=6b7d62e87ebc0f438e02a66b9011a26fffe827bd;p=thirdparty%2Fsamba.git CVE-2020-25719 s4:kdc: Check if the pac is valid before updating it BUG: https://bugzilla.samba.org/show_bug.cgi?id=14561 Signed-off-by: Andreas Schneider Reviewed-by: Andrew Bartlett --- diff --git a/selftest/knownfail_heimdal_kdc b/selftest/knownfail_heimdal_kdc index 850346940ad..75ca4bba8c4 100644 --- a/selftest/knownfail_heimdal_kdc +++ b/selftest/knownfail_heimdal_kdc @@ -271,13 +271,6 @@ ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_remove_pac_service_no_auth_data_required ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_request_no_pac # -# Alias tests -# -^samba.tests.krb5.alias_tests.samba.tests.krb5.alias_tests.AliasTests.test_create_alias_delete -^samba.tests.krb5.alias_tests.samba.tests.krb5.alias_tests.AliasTests.test_create_alias_rename -^samba.tests.krb5.alias_tests.samba.tests.krb5.alias_tests.AliasTests.test_dc_alias_delete -^samba.tests.krb5.alias_tests.samba.tests.krb5.alias_tests.AliasTests.test_dc_alias_rename -# # KDC TGT tests # ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_renew_authdata_no_pac @@ -288,10 +281,6 @@ ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_renew_rodc_no_partial_secrets ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_renew_rodc_not_allowed ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_renew_rodc_not_revealed -^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_renew_rodc_sid_mismatch_existing -^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_renew_rodc_sid_mismatch_nonexisting -^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_renew_sid_mismatch_existing -^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_renew_sid_mismatch_nonexisting ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_s4u2self_authdata_no_pac ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_s4u2self_no_pac ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_s4u2self_rodc_allowed_denied @@ -300,10 +289,6 @@ ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_s4u2self_rodc_no_partial_secrets ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_s4u2self_rodc_not_allowed ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_s4u2self_rodc_not_revealed -^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_s4u2self_rodc_sid_mismatch_existing -^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_s4u2self_rodc_sid_mismatch_nonexisting -^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_s4u2self_sid_mismatch_existing -^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_s4u2self_sid_mismatch_nonexisting ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_tgs_authdata_no_pac ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_tgs_no_pac ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_tgs_rodc_allowed_denied @@ -312,10 +297,6 @@ ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_tgs_rodc_no_partial_secrets ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_tgs_rodc_not_allowed ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_tgs_rodc_not_revealed -^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_tgs_rodc_sid_mismatch_existing -^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_tgs_rodc_sid_mismatch_nonexisting -^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_tgs_sid_mismatch_existing -^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_tgs_sid_mismatch_nonexisting ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_upn_dns_info_ex_mac ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_upn_dns_info_ex_upn_mac ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_upn_dns_info_ex_upn_user @@ -354,10 +335,6 @@ ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_validate_rodc_no_partial_secrets ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_validate_rodc_not_allowed ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_validate_rodc_not_revealed -^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_validate_rodc_sid_mismatch_existing -^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_validate_rodc_sid_mismatch_nonexisting -^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_validate_sid_mismatch_existing -^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_validate_sid_mismatch_nonexisting # # PAC attributes tests # @@ -392,8 +369,8 @@ # PAC requester SID tests # ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_as_requester_sid -^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_logon_info_only_sid_mismatch_existing -^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_logon_info_only_sid_mismatch_nonexisting +^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_logon_info_sid_mismatch_existing +^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_logon_info_sid_mismatch_nonexisting ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_requester_sid_mismatch_existing ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_requester_sid_mismatch_nonexisting ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_tgs_req_from_rodc_no_requester_sid @@ -402,8 +379,8 @@ ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_tgs_requester_sid_missing_rodc_renew ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_tgs_requester_sid_renew ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_tgs_requester_sid_rodc_renew -^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_tgs_rodc_logon_info_only_sid_mismatch_existing -^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_tgs_rodc_logon_info_only_sid_mismatch_nonexisting +^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_tgs_rodc_logon_info_sid_mismatch_existing +^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_tgs_rodc_logon_info_sid_mismatch_nonexisting ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_tgs_rodc_requester_sid_mismatch_existing ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_tgs_rodc_requester_sid_mismatch_nonexisting # diff --git a/selftest/knownfail_mit_kdc b/selftest/knownfail_mit_kdc index 53aa05814c2..dfdd17c655a 100644 --- a/selftest/knownfail_mit_kdc +++ b/selftest/knownfail_mit_kdc @@ -407,8 +407,6 @@ samba.tests.krb5.as_canonicalization_tests.samba.tests.krb5.as_canonicalization_ ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_renew_rodc_revealed ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_renew_rodc_sid_mismatch_existing ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_renew_rodc_sid_mismatch_nonexisting -^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_renew_sid_mismatch_existing -^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_renew_sid_mismatch_nonexisting ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_s4u2self_authdata_no_pac ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_s4u2self_no_pac ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_s4u2self_req @@ -434,8 +432,6 @@ samba.tests.krb5.as_canonicalization_tests.samba.tests.krb5.as_canonicalization_ ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_tgs_rodc_revealed ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_tgs_rodc_sid_mismatch_existing ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_tgs_rodc_sid_mismatch_nonexisting -^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_tgs_sid_mismatch_existing -^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_tgs_sid_mismatch_nonexisting ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_upn_dns_info_ex_mac ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_upn_dns_info_ex_upn_mac ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_upn_dns_info_ex_upn_user @@ -475,8 +471,6 @@ samba.tests.krb5.as_canonicalization_tests.samba.tests.krb5.as_canonicalization_ ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_validate_rodc_revealed ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_validate_rodc_sid_mismatch_existing ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_validate_rodc_sid_mismatch_nonexisting -^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_validate_sid_mismatch_existing -^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_validate_sid_mismatch_nonexisting # # PAC attributes tests # @@ -518,8 +512,8 @@ samba.tests.krb5.as_canonicalization_tests.samba.tests.krb5.as_canonicalization_ # PAC requester SID tests # ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_as_requester_sid -^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_logon_info_only_sid_mismatch_existing -^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_logon_info_only_sid_mismatch_nonexisting +^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_logon_info_sid_mismatch_existing +^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_logon_info_sid_mismatch_nonexisting ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_requester_sid_mismatch_existing ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_requester_sid_mismatch_nonexisting ^samba.tests.krb5.kdc_tgs_tests.samba.tests.krb5.kdc_tgs_tests.KdcTgsTests.test_tgs_req_from_rodc_no_requester_sid diff --git a/source4/kdc/mit_samba.c b/source4/kdc/mit_samba.c index d0e68ec8ea4..592f6a3bac4 100644 --- a/source4/kdc/mit_samba.c +++ b/source4/kdc/mit_samba.c @@ -512,6 +512,15 @@ krb5_error_code mit_samba_reget_pac(struct mit_samba_context *ctx, client_skdc_entry = talloc_get_type_abort(client->e_data, struct samba_kdc_entry); + + /* + * Check the objectSID of the client and pac data are the same. + * Does a parse and SID check, but no crypto. + */ + code = samba_kdc_validate_pac_blob(context, client_skdc_entry, *pac); + if (code != 0) { + goto done; + } } if (server == NULL) { diff --git a/source4/kdc/wdc-samba4.c b/source4/kdc/wdc-samba4.c index ac9d7d51733..ed6e9fb9b63 100644 --- a/source4/kdc/wdc-samba4.c +++ b/source4/kdc/wdc-samba4.c @@ -137,6 +137,23 @@ static krb5_error_code samba_wdc_reget_pac2(krb5_context context, return ENOMEM; } + if (client != NULL) { + struct samba_kdc_entry *client_skdc_entry = NULL; + + client_skdc_entry = talloc_get_type_abort(client->ctx, + struct samba_kdc_entry); + + /* + * Check the objectSID of the client and pac data are the same. + * Does a parse and SID check, but no crypto. + */ + ret = samba_kdc_validate_pac_blob(context, client_skdc_entry, *pac); + if (ret != 0) { + talloc_free(mem_ctx); + return ret; + } + } + /* If the krbtgt was generated by an RODC, and we are not that * RODC, then we need to regenerate the PAC - we can't trust * it */