diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
index 9f82fe0e6270..11f049e5410a 100644
--- a/net/bluetooth/hci_event.c
+++ b/net/bluetooth/hci_event.c
@@ -4173,6 +4173,15 @@ static void hci_link_key_notify_evt(struct hci_dev *hdev, struct sk_buff *skb)
 	if (!conn)
 		goto unlock;
 
+	/* Ignore NULL link key against CVE-2020-26555 */
+	if (!memcmp(ev->link_key, ZERO_KEY, HCI_LINK_KEY_SIZE)) {
+		bt_dev_dbg(hdev, "Ignore NULL link key (ZERO KEY) for %pMR",
+			   &ev->bdaddr);
+		hci_disconnect(conn, HCI_ERROR_AUTH_FAILURE);
+		hci_conn_drop(conn);
+		goto unlock;
+	}
+
 	hci_conn_hold(conn);
 	conn->disc_timeout = HCI_DISCONN_TIMEOUT;
 	hci_conn_drop(conn);