diff options
Diffstat (limited to 'main/krb5/CVE-2018-20217.patch')
| -rw-r--r-- | main/krb5/CVE-2018-20217.patch | 72 |
1 files changed, 72 insertions, 0 deletions
diff --git a/main/krb5/CVE-2018-20217.patch b/main/krb5/CVE-2018-20217.patch new file mode 100644 index 0000000000..80f2d55058 --- /dev/null +++ b/main/krb5/CVE-2018-20217.patch @@ -0,0 +1,72 @@ +From 5e6d1796106df8ba6bc1973ee0917c170d929086 Mon Sep 17 00:00:00 2001 +From: Isaac Boukris <iboukris@gmail.com> +Date: Mon, 3 Dec 2018 02:33:07 +0200 +Subject: [PATCH] Ignore password attributes for S4U2Self requests + +For consistency with Windows KDCs, allow protocol transition to work +even if the password has expired or needs changing. + +Also, when looking up an enterprise principal with an AS request, +treat ERR_KEY_EXP as confirmation that the client is present in the +realm. + +[ghudson@mit.edu: added comment in kdc_process_s4u2self_req(); edited +commit message] + +ticket: 8763 (new) +tags: pullup +target_version: 1.17 +--- + src/kdc/kdc_util.c | 5 +++++ + src/lib/krb5/krb/s4u_creds.c | 2 +- + src/tests/gssapi/t_s4u.py | 8 ++++++++ + 3 files changed, 14 insertions(+), 1 deletion(-) + +diff --git a/src/kdc/kdc_util.c b/src/kdc/kdc_util.c +index 6d53173fb0..6517a213cd 100644 +--- a/src/kdc/kdc_util.c ++++ b/src/kdc/kdc_util.c +@@ -1607,6 +1607,11 @@ kdc_process_s4u2self_req(kdc_realm_t *kdc_active_realm, + + memset(&no_server, 0, sizeof(no_server)); + ++ /* Ignore password expiration and needchange attributes (as Windows ++ * does), since S4U2Self is not password authentication. */ ++ princ->pw_expiration = 0; ++ clear(princ->attributes, KRB5_KDB_REQUIRES_PWCHANGE); ++ + code = validate_as_request(kdc_active_realm, request, *princ, + no_server, kdc_time, status, &e_data); + if (code) { +diff --git a/src/lib/krb5/krb/s4u_creds.c b/src/lib/krb5/krb/s4u_creds.c +index d2fdcb3f16..614ed41908 100644 +--- a/src/lib/krb5/krb/s4u_creds.c ++++ b/src/lib/krb5/krb/s4u_creds.c +@@ -116,7 +116,7 @@ s4u_identify_user(krb5_context context, + code = k5_get_init_creds(context, &creds, &client, NULL, NULL, 0, NULL, + opts, krb5_get_as_key_noop, &userid, &use_master, + NULL); +- if (code == 0 || code == KRB5_PREAUTH_FAILED) { ++ if (!code || code == KRB5_PREAUTH_FAILED || code == KRB5KDC_ERR_KEY_EXP) { + *canon_user = userid.user; + userid.user = NULL; + code = 0; +diff --git a/src/tests/gssapi/t_s4u.py b/src/tests/gssapi/t_s4u.py +index fd29e1a270..84f3fbd752 100755 +--- a/src/tests/gssapi/t_s4u.py ++++ b/src/tests/gssapi/t_s4u.py +@@ -19,6 +19,14 @@ + # Get forwardable creds for service1 in the default cache. + realm.kinit(service1, None, ['-f', '-k']) + ++# Try S4U2Self for user with a restricted password. ++realm.run([kadminl, 'modprinc', '+needchange', realm.user_princ]) ++realm.run(['./t_s4u', 'e:user', '-']) ++realm.run([kadminl, 'modprinc', '-needchange', ++ '-pwexpire', '1/1/2000', realm.user_princ]) ++realm.run(['./t_s4u', 'e:user', '-']) ++realm.run([kadminl, 'modprinc', '-pwexpire', 'never', realm.user_princ]) ++ + # Try krb5 -> S4U2Proxy with forwardable user creds. This should fail + # at the S4U2Proxy step since the DB2 back end currently has no + # support for allowing it. |