diff --git a/lib/tls/mbedtls/mbedtls-server.c b/lib/tls/mbedtls/mbedtls-server.c
index a972952b9..0af459ca1 100644
--- a/lib/tls/mbedtls/mbedtls-server.c
+++ b/lib/tls/mbedtls/mbedtls-server.c
@@ -39,7 +39,7 @@ lws_tls_server_client_cert_verify_config(struct lws_vhost *vh)
 	}
 
 	if (!lws_check_opt(vh->options, LWS_SERVER_OPTION_PEER_CERT_NOT_REQUIRED))
-		verify_options = SSL_VERIFY_FAIL_IF_NO_PEER_CERT;
+		verify_options |= SSL_VERIFY_FAIL_IF_NO_PEER_CERT;
 
 	lwsl_notice("%s: vh %s requires client cert %d\n", __func__, vh->name,
 		    verify_options);