diff --git a/lib/openssl/ssl.rb b/lib/openssl/ssl.rb
index b77f0b52..697183ab 100644
--- a/lib/openssl/ssl.rb
+++ b/lib/openssl/ssl.rb
@@ -314,7 +314,7 @@ def verify_hostname(hostname, san) # :nodoc:
       san_parts = san.downcase.split(".")
 
       # TODO: this behavior should probably be more strict
-      return san == hostname if san_parts.size < 2
+      return san.downcase == hostname.downcase if san_parts.size < 2
 
       # Matching is case-insensitive.
       host_parts = hostname.downcase.split(".")