diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c
index 3b87e978d972..30137d1b0d8d 100644
--- a/drivers/usb/class/cdc-acm.c
+++ b/drivers/usb/class/cdc-acm.c
@@ -1241,9 +1241,21 @@ static int acm_probe(struct usb_interface *intf,
 			}
 		}
 	} else {
+		int class = -1;
+
 		data_intf_num = union_header->bSlaveInterface0;
 		control_interface = usb_ifnum_to_if(usb_dev, union_header->bMasterInterface0);
 		data_interface = usb_ifnum_to_if(usb_dev, data_intf_num);
+
+		if (control_interface)
+			class = control_interface->cur_altsetting->desc.bInterfaceClass;
+
+		if (class != USB_CLASS_COMM && class != USB_CLASS_CDC_DATA) {
+			dev_dbg(&intf->dev, "Broken union descriptor, assuming single interface\n");
+			combined_interfaces = 1;
+			control_interface = data_interface = intf;
+			goto look_for_collapsed_interface;
+		}
 	}
 
 	if (!control_interface || !data_interface) {