diff --git a/firmware/messages.c b/firmware/messages.c
index 15c510bd9..d8411bfa8 100644
--- a/firmware/messages.c
+++ b/firmware/messages.c
@@ -222,7 +222,7 @@ enum {
 
 void msg_process(char type, uint16_t msg_id, const pb_field_t *fields, uint8_t *msg_raw, uint32_t msg_size)
 {
-	static uint8_t msg_data[MSG_IN_SIZE];
+	static CONFIDENTIAL uint8_t msg_data[MSG_IN_SIZE];
 	memset(msg_data, 0, sizeof(msg_data));
 	pb_istream_t stream = pb_istream_from_buffer(msg_raw, msg_size);
 	bool status = pb_decode(&stream, fields, msg_data);
@@ -236,7 +236,7 @@ void msg_process(char type, uint16_t msg_id, const pb_field_t *fields, uint8_t *
 void msg_read_common(char type, const uint8_t *buf, int len)
 {
 	static char read_state = READSTATE_IDLE;
-	static uint8_t msg_in[MSG_IN_SIZE];
+	static CONFIDENTIAL uint8_t msg_in[MSG_IN_SIZE];
 	static uint16_t msg_id = 0xFFFF;
 	static uint32_t msg_size = 0;
 	static uint32_t msg_pos = 0;
@@ -304,7 +304,7 @@ const uint8_t *msg_debug_out_data(void)
 
 #endif
 
-uint8_t msg_tiny[64];
+CONFIDENTIAL uint8_t msg_tiny[64];
 uint16_t msg_tiny_id = 0xFFFF;
 
 void msg_read_tiny(const uint8_t *buf, int len)
diff --git a/firmware/usb.c b/firmware/usb.c
index deae841d6..55bd09517 100644
--- a/firmware/usb.c
+++ b/firmware/usb.c
@@ -343,7 +343,7 @@ static volatile char tiny = 0;
 static void hid_rx_callback(usbd_device *dev, uint8_t ep)
 {
 	(void)ep;
-	static uint8_t buf[64] __attribute__ ((aligned(4)));
+	static CONFIDENTIAL uint8_t buf[64] __attribute__ ((aligned(4)));
 	if ( usbd_ep_read_packet(dev, ENDPOINT_ADDRESS_OUT, buf, 64) != 64) return;
 	debugLog(0, "", "hid_rx_callback");
 	if (!tiny) {
@@ -356,7 +356,7 @@ static void hid_rx_callback(usbd_device *dev, uint8_t ep)
 static void hid_u2f_rx_callback(usbd_device *dev, uint8_t ep)
 {
 	(void)ep;
-	static uint8_t buf[64] __attribute__ ((aligned(4)));
+	static CONFIDENTIAL uint8_t buf[64] __attribute__ ((aligned(4)));
 
 	debugLog(0, "", "hid_u2f_rx_callback");
 	if ( usbd_ep_read_packet(dev, ENDPOINT_ADDRESS_U2F_OUT, buf, 64) != 64) return;
@@ -367,7 +367,7 @@ static void hid_u2f_rx_callback(usbd_device *dev, uint8_t ep)
 static void hid_debug_rx_callback(usbd_device *dev, uint8_t ep)
 {
 	(void)ep;
-	static uint8_t buf[64] __attribute__ ((aligned(4)));
+	static CONFIDENTIAL uint8_t buf[64] __attribute__ ((aligned(4)));
 	if ( usbd_ep_read_packet(dev, ENDPOINT_ADDRESS_DEBUG_OUT, buf, 64) != 64) return;
 	debugLog(0, "", "hid_debug_rx_callback");
 	if (!tiny) {