diff --git a/docs/development/test-vectors.rst b/docs/development/test-vectors.rst
index 3d49801..824fb57 100644
--- a/docs/development/test-vectors.rst
+++ b/docs/development/test-vectors.rst
@@ -192,6 +192,9 @@
   text and no notice reference.
 * ``cp_cps_uri.pem`` - An RSA 2048 bit self-signed certificate containing a
   certificate policies extension with a CPS URI and no user notice.
+* ``cp_user_notice_no_explicit_text.pem`` - An RSA 2048 bit self-signed
+  certificate containing a certificate policies extension with a user notice
+  with no explicit text.
 
 Custom X.509 Request Vectors
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
diff --git a/src/cryptography/hazmat/backends/openssl/x509.py b/src/cryptography/hazmat/backends/openssl/x509.py
index 25b7c8c..8b5f392 100644
--- a/src/cryptography/hazmat/backends/openssl/x509.py
+++ b/src/cryptography/hazmat/backends/openssl/x509.py
@@ -45,6 +45,17 @@
     return backend._bn_to_int(bn)
 
 
+def _asn1_string_to_utf8(backend, asn1_string):
+    buf = backend._ffi.new("unsigned char **")
+    res = backend._lib.ASN1_STRING_to_UTF8(buf, asn1_string)
+    assert res >= 0
+    assert buf[0] != backend._ffi.NULL
+    buf = backend._ffi.gc(
+        buf, lambda buffer: backend._lib.OPENSSL_free(buffer[0])
+    )
+    return backend._ffi.buffer(buf[0], res)[:].decode('utf8')
+
+
 def _build_x509_name(backend, x509_name):
     count = backend._lib.X509_NAME_entry_count(x509_name)
     attributes = []
@@ -54,14 +65,7 @@
         assert obj != backend._ffi.NULL
         data = backend._lib.X509_NAME_ENTRY_get_data(entry)
         assert data != backend._ffi.NULL
-        buf = backend._ffi.new("unsigned char **")
-        res = backend._lib.ASN1_STRING_to_UTF8(buf, data)
-        assert res >= 0
-        assert buf[0] != backend._ffi.NULL
-        buf = backend._ffi.gc(
-            buf, lambda buffer: backend._lib.OPENSSL_free(buffer[0])
-        )
-        value = backend._ffi.buffer(buf[0], res)[:].decode('utf8')
+        value = _asn1_string_to_utf8(backend, data)
         oid = _obj2txt(backend, obj)
         attributes.append(
             x509.NameAttribute(
diff --git a/src/cryptography/hazmat/bindings/openssl/x509v3.py b/src/cryptography/hazmat/bindings/openssl/x509v3.py
index 4f9eca8..2316799 100644
--- a/src/cryptography/hazmat/bindings/openssl/x509v3.py
+++ b/src/cryptography/hazmat/bindings/openssl/x509v3.py
@@ -151,9 +151,6 @@
     ASN1_OBJECT *policyid;
     Cryptography_STACK_OF_POLICYQUALINFO *qualifiers;
 } POLICYINFO;
-
-typedef Cryptography_STACK_OF_POLICYINFO CERTIFICATEPOLICIES;
-
 """
 
 
@@ -194,6 +191,19 @@
 void sk_DIST_POINT_free(Cryptography_STACK_OF_DIST_POINT *);
 int sk_DIST_POINT_num(Cryptography_STACK_OF_DIST_POINT *);
 DIST_POINT *sk_DIST_POINT_value(Cryptography_STACK_OF_DIST_POINT *, int);
+
+void sk_POLICYINFO_free(Cryptography_STACK_OF_POLICYINFO *);
+int sk_POLICYINFO_num(Cryptography_STACK_OF_POLICYINFO *);
+POLICYINFO *sk_POLICYINFO_value(Cryptography_STACK_OF_POLICYINFO *, int);
+
+void sk_POLICYQUALINFO_free(Cryptography_STACK_OF_POLICYQUALINFO *);
+int sk_POLICYQUALINFO_num(Cryptography_STACK_OF_POLICYQUALINFO *);
+POLICYQUALINFO *sk_POLICYQUALINFO_value(Cryptography_STACK_OF_POLICYQUALINFO *,
+                                        int);
+
+void sk_ASN1_INTEGER_free(Cryptography_STACK_OF_ASN1_INTEGER *);
+int sk_ASN1_INTEGER_num(Cryptography_STACK_OF_ASN1_INTEGER *);
+ASN1_INTEGER *sk_ASN1_INTEGER_value(Cryptography_STACK_OF_ASN1_INTEGER *, int);
 """
 
 CUSTOMIZATIONS = """
diff --git a/tox.ini b/tox.ini
index 759345f..77382eb 100644
--- a/tox.ini
+++ b/tox.ini
@@ -9,6 +9,7 @@
     pretend
     pytest
     ./vectors
+passenv = ARCHFLAGS LDFLAGS CFLAGS INCLUDE LIB LD_LIBRARY_PATH
 commands =
     # We use parallel mode and then combine here so that coverage.py will take
     # the paths like .tox/py34/lib/python3.4/site-packages/cryptography/__init__.py
diff --git a/vectors/cryptography_vectors/x509/custom/cp_user_notice_no_explicit_text.pem b/vectors/cryptography_vectors/x509/custom/cp_user_notice_no_explicit_text.pem
new file mode 100644
index 0000000..2e83f4f
--- /dev/null
+++ b/vectors/cryptography_vectors/x509/custom/cp_user_notice_no_explicit_text.pem
@@ -0,0 +1,18 @@
+-----BEGIN CERTIFICATE-----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+-----END CERTIFICATE-----