diff --git a/strongswan-5.2.2-5.3.0_unknown_payload.patch b/0005-strongswan-5.2.2-5.3.0_unknown_payload.patch
similarity index 100%
rename from strongswan-5.2.2-5.3.0_unknown_payload.patch
rename to 0005-strongswan-5.2.2-5.3.0_unknown_payload.patch
diff --git a/0006-strongswan-5.1.0-5.3.1_enforce_remote_auth.patch b/0006-strongswan-5.1.0-5.3.1_enforce_remote_auth.patch
new file mode 100644
index 0000000..2d35f9c
--- /dev/null
+++ b/0006-strongswan-5.1.0-5.3.1_enforce_remote_auth.patch
@@ -0,0 +1,102 @@
+From ca1a65cc6aef2e037b529574783b7c571d1d82a9 Mon Sep 17 00:00:00 2001
+From: Martin Willi <martin@strongswan.org>
+Date: Wed, 3 Jun 2015 10:52:34 +0200
+References: bsc#933591,CVE-2015-4171
+Subject: [PATCH] ikev2: Enforce remote authentication config before proceeding
+ with own authentication
+
+Previously the constraints in the authentication configuration of an
+initiator were enforced only after all authentication rounds were
+complete.  This posed a problem if an initiator used EAP or PSK
+authentication while the responder was authenticated with a certificate
+and if a rogue server was able to authenticate itself with a valid
+certificate issued by any CA the initiator trusted.
+
+Because any constraints for the responder's identity (rightid) or other
+aspects of the authentication (e.g. rightca) the initiator had were not
+enforced until the initiator itself finished its authentication such a rogue
+responder was able to acquire usernames and password hashes from the client.
+And if a client supported EAP-GTC it was even possible to trick it into
+sending plaintext passwords.
+
+This patch enforces the configured constraints right after the responder's
+authentication successfully finished for each round and before the initiator
+starts with its own authentication.
+
+Fixes CVE-2015-4171.
+---
+ src/libcharon/sa/ikev2/tasks/ike_auth.c | 44 +++++++++++++++++++++++++++++++++
+ 1 file changed, 44 insertions(+)
+
+diff --git a/src/libcharon/sa/ikev2/tasks/ike_auth.c b/src/libcharon/sa/ikev2/tasks/ike_auth.c
+index bf747a49edde..2554496c1916 100644
+--- a/src/libcharon/sa/ikev2/tasks/ike_auth.c
++++ b/src/libcharon/sa/ikev2/tasks/ike_auth.c
+@@ -112,6 +112,11 @@ struct private_ike_auth_t {
+ 	 * received an INITIAL_CONTACT?
+ 	 */
+ 	bool initial_contact;
++
++	/**
++	 * Is EAP acceptable, did we strictly authenticate peer?
++	 */
++	bool eap_acceptable;
+ };
+ 
+ /**
+@@ -879,6 +884,37 @@ static void send_auth_failed_informational(private_ike_auth_t *this,
+ 	message->destroy(message);
+ }
+ 
++/**
++ * Check if strict constraint fullfillment required to continue current auth
++ */
++static bool require_strict(private_ike_auth_t *this, bool mutual_eap)
++{
++	auth_cfg_t *cfg;
++
++	if (this->eap_acceptable)
++	{
++		return FALSE;
++	}
++
++	cfg = this->ike_sa->get_auth_cfg(this->ike_sa, TRUE);
++	switch ((uintptr_t)cfg->get(cfg, AUTH_RULE_AUTH_CLASS))
++	{
++		case AUTH_CLASS_EAP:
++			if (mutual_eap && this->my_auth)
++			{
++				this->eap_acceptable = TRUE;
++				return !this->my_auth->is_mutual(this->my_auth);
++			}
++			return TRUE;
++		case AUTH_CLASS_PSK:
++			return TRUE;
++		case AUTH_CLASS_PUBKEY:
++		case AUTH_CLASS_ANY:
++		default:
++			return FALSE;
++	}
++}
++
+ METHOD(task_t, process_i, status_t,
+ 	private_ike_auth_t *this, message_t *message)
+ {
+@@ -1014,6 +1050,14 @@ METHOD(task_t, process_i, status_t,
+ 		}
+ 	}
+ 
++	if (require_strict(this, mutual_eap))
++	{
++		if (!update_cfg_candidates(this, TRUE))
++		{
++			goto peer_auth_failed;
++		}
++	}
++
+ 	if (this->my_auth)
+ 	{
+ 		switch (this->my_auth->process(this->my_auth, message))
+-- 
+1.9.1
+
diff --git a/strongswan.changes b/strongswan.changes
index c8f651a..c7d63f5 100644
--- a/strongswan.changes
+++ b/strongswan.changes
@@ -1,3 +1,16 @@
+-------------------------------------------------------------------
+Thu Jun  4 10:54:29 UTC 2015 - mt@suse.de
+
+- Applied upstream fix for a rogue servers vulnerability, that may
+  enable rogue servers able to authenticate itself with certificate
+  issued by any CA the client trusts, to gain user credentials from
+  a client in certain IKEv2 setups (bsc#933591,CVE-2015-4171).
+  [+ 0006-strongswan-5.1.0-5.3.1_enforce_remote_auth.patch]
+- Fix to apply unknown_payload patch if fips is disabled (<= 13.1)
+  and renamed it to use number prefix corresponding with patch nr.
+  [- strongswan-5.2.2-5.3.0_unknown_payload.patch,
+   + 0005-strongswan-5.2.2-5.3.0_unknown_payload.patch]
+
 -------------------------------------------------------------------
 Mon Jun  1 16:18:35 UTC 2015 - mt@suse.de
 
diff --git a/strongswan.spec b/strongswan.spec
index 93c5503..76df96b 100644
--- a/strongswan.spec
+++ b/strongswan.spec
@@ -82,7 +82,8 @@ Patch2:         %{name}_ipsec_service.patch
 Patch3:         %{name}_fipscheck.patch
 Patch4:         %{name}_fipsfilter.patch
 %endif
-Patch5:         %{name}-5.2.2-5.3.0_unknown_payload.patch
+Patch5:         0005-strongswan-5.2.2-5.3.0_unknown_payload.patch
+Patch6:         0006-strongswan-5.1.0-5.3.1_enforce_remote_auth.patch
 BuildRoot:      %{_tmppath}/%{name}-%{version}-build
 BuildRequires:  bison
 BuildRequires:  curl-devel
@@ -292,8 +293,9 @@ and the load testing plugin for IKEv2 daemon.
 %if %{with fipscheck}
 %patch3 -p0
 %patch4 -p1
-%patch5 -p1
 %endif
+%patch5 -p1
+%patch6 -p1
 sed -e 's|@libexecdir@|%_libexecdir|g'    \
      < $RPM_SOURCE_DIR/strongswan.init.in \
      > strongswan.init