diff --git a/common/usb_kbd.c b/common/usb_kbd.c
index 36107a3b278..c037359260a 100644
--- a/common/usb_kbd.c
+++ b/common/usb_kbd.c
@@ -626,6 +626,14 @@ static int probe_usb_keyboard(struct usb_device *dev)
 		return error;
 
 	stdinname = env_get("stdin");
+	if (!stdinname) {
+		/*
+		 * `stdin` can be unset in the default env, so don't
+		 * crash if a USB keyboard happens to be plugged in.
+		 */
+		return 0;
+	}
+
 #if CONFIG_IS_ENABLED(CONSOLE_MUX)
 	if (strstr(stdinname, DEVNAME) != NULL) {
 		error = iomux_doenv(stdin, stdinname);