diff --git a/subsys/bluetooth/common/Kconfig b/subsys/bluetooth/common/Kconfig
index 8bec5ba90d5d8..a2ab25a99c571 100644
--- a/subsys/bluetooth/common/Kconfig
+++ b/subsys/bluetooth/common/Kconfig
@@ -173,6 +173,7 @@ config BT_BUF_CMD_TX_SIZE
 
 config BT_BUF_CMD_TX_COUNT
 	int "Number of HCI command buffers"
+	default 3 if BT_EXT_ADV && BT_CENTRAL
 	default 2
 	range 2 64
 	help
diff --git a/subsys/bluetooth/host/hci_core.c b/subsys/bluetooth/host/hci_core.c
index 4606c8c9b1f1c..61abec0af4ab1 100644
--- a/subsys/bluetooth/host/hci_core.c
+++ b/subsys/bluetooth/host/hci_core.c
@@ -891,6 +891,9 @@ int bt_le_create_conn_cancel(void)
 	struct bt_hci_cmd_state_set state;
 
 	buf = bt_hci_cmd_create(BT_HCI_OP_LE_CREATE_CONN_CANCEL, 0);
+	if (!buf) {
+		return -ENOBUFS;
+	}
 
 	bt_hci_cmd_state_set_init(buf, &state, bt_dev.flags,
 				  BT_DEV_INITIATING, false);