diff --git a/0013-intg-convert-results-returned-as-bytes-to-strings.patch b/0013-intg-convert-results-returned-as-bytes-to-strings.patch
new file mode 100644
index 0000000..0174103
--- /dev/null
+++ b/0013-intg-convert-results-returned-as-bytes-to-strings.patch
@@ -0,0 +1,48 @@
+From 414ce6438a5450e5f1c1b03994f59d37f0ff8a36 Mon Sep 17 00:00:00 2001
+From: Lukas Slebodnik <lslebodn@redhat.com>
+Date: Fri, 16 Mar 2018 13:43:17 +0100
+Subject: [PATCH 13/15] intg: convert results returned as bytes to strings
+
+With python3 comparisons between byte literals and strings will fail. To
+make sure assertions will pass the search results must be converted to
+(utf-8) strings first.
+
+Resolves https://pagure.io/SSSD/sssd/issue/3666
+
+Reviewed-by: Sumit Bose <sbose@redhat.com>
+Reviewed-by: Jakub Hrozek <jhrozek@redhat.com>
+---
+ src/tests/intg/test_ts_cache.py | 17 +++++++++++------
+ 1 file changed, 11 insertions(+), 6 deletions(-)
+
+diff --git a/src/tests/intg/test_ts_cache.py b/src/tests/intg/test_ts_cache.py
+index 703e3b255..c3819e21a 100644
+--- a/src/tests/intg/test_ts_cache.py
++++ b/src/tests/intg/test_ts_cache.py
+@@ -212,12 +212,17 @@ def get_attrs(ldb_conn, type, name, domain, attr_list):
+     ts_attrs = dict()
+ 
+     for attr in attr_list:
+-        sysdb_attrs[attr] = ldb_conn.get_entry_attr(
+-                                     sssd_ldb.CacheType.sysdb,
+-                                     type, name, domain, attr)
+-        ts_attrs[attr] = ldb_conn.get_entry_attr(
+-                                     sssd_ldb.CacheType.timestamps,
+-                                     type, name, domain, attr)
++        val = ldb_conn.get_entry_attr(sssd_ldb.CacheType.sysdb,
++                                      type, name, domain, attr)
++        if val:
++            val = val.decode('utf-8')
++        sysdb_attrs[attr] = val
++
++        val = ldb_conn.get_entry_attr(sssd_ldb.CacheType.timestamps,
++                                      type, name, domain, attr)
++        if val:
++            val = val.decode('utf-8')
++        ts_attrs[attr] = val
+     return (sysdb_attrs, ts_attrs)
+ 
+ 
+-- 
+2.14.3
+
diff --git a/sssd.spec b/sssd.spec
index a4e74d6..17d7d24 100644
--- a/sssd.spec
+++ b/sssd.spec
@@ -54,6 +54,7 @@ Patch0009: 0009-KCM-Remove-mem_ctx-from-kcm_new_req.patch
 Patch0010: 0010-KCM-Introduce-kcm_input_get_payload_len.patch
 Patch0011: 0011-KCM-Do-not-use-2048-as-fixed-size-for-the-payload.patch
 Patch0012: 0012-KCM-Adjust-REPLY_MAX-to-the-one-used-in-krb5.patch
+Patch0013: 0013-intg-convert-results-returned-as-bytes-to-strings.patch
 
 Patch0502: 0502-SYSTEMD-Use-capabilities.patch
 Patch0503: 0503-Disable-stopping-idle-socket-activated-responders.patch
@@ -1261,6 +1262,7 @@ fi
 - Resolves: upstream#3687 - KCM: Don't pass a non null terminated string to
                             json_loads()
 - Resolves: upstream#3386 - KCM: Payload buffer is too small
+- Resolves: upstream#3666 - Fix usage of str.decode() in our tests
 
 * Fri Mar  9 2018 Fabiano Fidêncio <fidencio@fedoraproject.org> - 1.16.1-1
 - New upstream release 1.16.1