diff --git a/phpseclib/File/X509.php b/phpseclib/File/X509.php
index af66b217..9a70457b 100644
--- a/phpseclib/File/X509.php
+++ b/phpseclib/File/X509.php
@@ -3466,7 +3466,7 @@ class X509
 
         $altName = array();
 
-        if (isset($subject->domains) && count($subject->domains) > 1) {
+        if (isset($subject->domains) && count($subject->domains)) {
             $altName = array_map(array('\phpseclib\File\X509', '_dnsName'), $subject->domains);
         }