diff --git a/manifests/apache.pp b/manifests/apache.pp
index b3fec56..de6c501 100644
--- a/manifests/apache.pp
+++ b/manifests/apache.pp
@@ -53,7 +53,7 @@
   ]
 
   $api_additional_request_headers = $pulpcore::api_client_auth_cn_map.map |String $cn, String $pulp_user| {
-    "set ${remote_user_environ_header} \"${pulp_user}\" \"expr=%{SSL_CLIENT_S_DN_CN} == '${cn}'\""
+    "set ${remote_user_environ_header} \"${pulp_user}\" \"expr=%{tolower:SSL_CLIENT_S_DN_CN} == '${cn.downcase}'\""
   }
 
   $api_directory = {