diff --git a/drivers/usb/class/cdc-wdm.c b/drivers/usb/class/cdc-wdm.c
index 3771d6e6d0c..34e6108e1d4 100644
--- a/drivers/usb/class/cdc-wdm.c
+++ b/drivers/usb/class/cdc-wdm.c
@@ -652,7 +652,7 @@ next_desc:
 
 	iface = &intf->altsetting[0];
 	ep = &iface->endpoint[0].desc;
-	if (!usb_endpoint_is_int_in(ep)) {
+	if (!ep || !usb_endpoint_is_int_in(ep)) {
 		rv = -EINVAL;
 		goto err;
 	}