diff --git a/scst/src/dev_handlers/scst_vdisk.c b/scst/src/dev_handlers/scst_vdisk.c
index fc80c6db6..55b19ded0 100644
--- a/scst/src/dev_handlers/scst_vdisk.c
+++ b/scst/src/dev_handlers/scst_vdisk.c
@@ -8053,7 +8053,7 @@ static ssize_t vdev_sysfs_naa_id_store(struct kobject *kobj,
 	switch (c) {
 	case 0:
 	case 2 * 8:
-		if (strchr("1235cCdDeEfF", buf[0]))
+		if (strchr("235", buf[0]))
 			break;
 		else
 			goto out;