diff --git a/docs/development/test-vectors.rst b/docs/development/test-vectors.rst
index 2edf1fb..5d6a32e 100644
--- a/docs/development/test-vectors.rst
+++ b/docs/development/test-vectors.rst
@@ -92,6 +92,10 @@
   generated using OpenSSL.
 * ``ec_no_named_curve.pem`` - Contains an ECDSA certificate that does not have
   an embedded OID defining the curve.
+* ``all_supported_names.pem`` - An RSA 2048 bit certificate generated using
+  OpenSSL that contains a subject and issuer that have two of each supported
+  attribute type from :rfc:`5280`.
+* ``unsupported_subject_name.pem`` - An RSA 2048 bit self-signed CA certificate generated using OpenSSL that contains the unsupported "initials" name.
 
 Hashes
 ~~~~~~
diff --git a/vectors/cryptography_vectors/x509/custom/all_supported_names.pem b/vectors/cryptography_vectors/x509/custom/all_supported_names.pem
new file mode 100644
index 0000000..1582bda
--- /dev/null
+++ b/vectors/cryptography_vectors/x509/custom/all_supported_names.pem
@@ -0,0 +1,44 @@
+-----BEGIN CERTIFICATE-----
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+-----END CERTIFICATE-----
diff --git a/vectors/cryptography_vectors/x509/custom/unsupported_subject_name.pem b/vectors/cryptography_vectors/x509/custom/unsupported_subject_name.pem
new file mode 100644
index 0000000..1a55457
--- /dev/null
+++ b/vectors/cryptography_vectors/x509/custom/unsupported_subject_name.pem
@@ -0,0 +1,18 @@
+-----BEGIN CERTIFICATE-----
+MIIC3DCCAcQCCQCEI+LAvF24yTANBgkqhkiG9w0BAQUFADAwMSEwHwYDVQQDDBhV
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+-----END CERTIFICATE-----