diff --git a/common/usb_cdc.c b/common/usb_cdc.c
index e2787fb6..97551692 100644
--- a/common/usb_cdc.c
+++ b/common/usb_cdc.c
@@ -81,7 +81,7 @@ const char cfgDescriptor[] = {
 	0x01, // bNumEndpoints
 	0x02, // bInterfaceClass
 	0x02, // bInterfaceSubclass
-	0x00, // bInterfaceProtocol
+	0x01, // bInterfaceProtocol
 	0x00, // iInterface
 
 	/* Header Functional Descriptor */