add an extended key usage x509 vector
diff --git a/docs/development/test-vectors.rst b/docs/development/test-vectors.rst
index 622a9d7..e207551 100644
--- a/docs/development/test-vectors.rst
+++ b/docs/development/test-vectors.rst
@@ -140,6 +140,8 @@
subject alternative name extension with the ``registeredID`` general name.
* ``all_key_usages.pem`` - An RSA 2048 bit self-signed certificate containing
a key usage extension with all nine purposes set to true.
+* ``extended_key_usage.pem`` - An RSA 2048 bit self-signed certificate
+ containing an extended key usage extension with eight usages.
* ``san_idna_names.pem`` - An RSA 2048 bit self-signed certificate containing
a subject alternative name extension with ``rfc822Name``, ``dNSName``, and
``uniformResourceIdentifier`` general names with IDNA (:rfc:`5895`) encoding.