diff --git a/SConscript.boardloader b/SConscript.boardloader
index 7afaeb7494..dc96a28b4a 100644
--- a/SConscript.boardloader
+++ b/SConscript.boardloader
@@ -26,6 +26,7 @@ SOURCE_MOD += [
     'vendor/trezor-crypto/ed25519-donna/ed25519-donna-32bit-tables.c',
     'vendor/trezor-crypto/ed25519-donna/ed25519-donna-impl-base.c',
     'vendor/trezor-crypto/ed25519-donna/modm-donna-32bit.c',
+    'vendor/trezor-crypto/memzero.c',
     'vendor/trezor-crypto/sha2.c',
 ]
 
diff --git a/SConscript.bootloader b/SConscript.bootloader
index 232764a3fe..6df6d660cf 100644
--- a/SConscript.bootloader
+++ b/SConscript.bootloader
@@ -26,6 +26,7 @@ SOURCE_MOD += [
     'vendor/trezor-crypto/ed25519-donna/ed25519-donna-32bit-tables.c',
     'vendor/trezor-crypto/ed25519-donna/ed25519-donna-impl-base.c',
     'vendor/trezor-crypto/ed25519-donna/modm-donna-32bit.c',
+    'vendor/trezor-crypto/memzero.c',
     'vendor/trezor-crypto/sha2.c',
 ]
 
diff --git a/SConscript.firmware b/SConscript.firmware
index 71cda68973..f993db5afe 100644
--- a/SConscript.firmware
+++ b/SConscript.firmware
@@ -60,6 +60,7 @@ SOURCE_MOD += [
     'vendor/trezor-crypto/ed25519-donna/modm-donna-32bit.c',
     'vendor/trezor-crypto/hasher.c',
     'vendor/trezor-crypto/hmac.c',
+    'vendor/trezor-crypto/memzero.c',
     'vendor/trezor-crypto/nist256p1.c',
     'vendor/trezor-crypto/pbkdf2.c',
     'vendor/trezor-crypto/rand.c',
diff --git a/SConscript.unix b/SConscript.unix
index 735daf9755..292f03c3f6 100644
--- a/SConscript.unix
+++ b/SConscript.unix
@@ -59,6 +59,7 @@ SOURCE_MOD += [
     'vendor/trezor-crypto/ed25519-donna/modm-donna-32bit.c',
     'vendor/trezor-crypto/hasher.c',
     'vendor/trezor-crypto/hmac.c',
+    'vendor/trezor-crypto/memzero.c',
     'vendor/trezor-crypto/nist256p1.c',
     'vendor/trezor-crypto/pbkdf2.c',
     'vendor/trezor-crypto/rand.c',
diff --git a/embed/extmod/modtrezorcrypto/modtrezorcrypto-aes.h b/embed/extmod/modtrezorcrypto/modtrezorcrypto-aes.h
index e9c74ff8f1..207569d1a8 100644
--- a/embed/extmod/modtrezorcrypto/modtrezorcrypto-aes.h
+++ b/embed/extmod/modtrezorcrypto/modtrezorcrypto-aes.h
@@ -8,6 +8,7 @@
 #include "py/objstr.h"
 
 #include "aes/aes.h"
+#include "memzero.h"
 
 /// class AES:
 ///     '''
@@ -145,8 +146,8 @@ STATIC MP_DEFINE_CONST_FUN_OBJ_2(mod_trezorcrypto_AES_update_obj, mod_trezorcryp
 
 STATIC mp_obj_t mod_trezorcrypto_AES___del__(mp_obj_t self) {
     mp_obj_AES_t *o = MP_OBJ_TO_PTR(self);
-    explicit_bzero(&(o->ctx), sizeof(aes_encrypt_ctx));
-    explicit_bzero(o->iv, AES_BLOCK_SIZE);
+    memzero(&(o->ctx), sizeof(aes_encrypt_ctx));
+    memzero(o->iv, AES_BLOCK_SIZE);
     return mp_const_none;
 }
 STATIC MP_DEFINE_CONST_FUN_OBJ_1(mod_trezorcrypto_AES___del___obj, mod_trezorcrypto_AES___del__);
diff --git a/embed/extmod/modtrezorcrypto/modtrezorcrypto-bip32.h b/embed/extmod/modtrezorcrypto/modtrezorcrypto-bip32.h
index 7b327a8031..6ff5809b69 100644
--- a/embed/extmod/modtrezorcrypto/modtrezorcrypto-bip32.h
+++ b/embed/extmod/modtrezorcrypto/modtrezorcrypto-bip32.h
@@ -9,6 +9,7 @@
 
 #include "bip32.h"
 #include "curves.h"
+#include "memzero.h"
 
 /// class HDNode:
 ///     '''
@@ -93,17 +94,17 @@ STATIC mp_obj_t mod_trezorcrypto_HDNode_make_new(const mp_obj_type_t *type, size
     if (NULL != chain_code.buf && 32 == chain_code.len) {
         memcpy(o->hdnode.chain_code, chain_code.buf, 32);
     } else {
-        explicit_bzero(o->hdnode.chain_code, 32);
+        memzero(o->hdnode.chain_code, 32);
     }
     if (NULL != private_key.buf && 32 == private_key.len) {
         memcpy(o->hdnode.private_key, private_key.buf, 32);
     } else {
-        explicit_bzero(o->hdnode.private_key, 32);
+        memzero(o->hdnode.private_key, 32);
     }
     if (NULL != public_key.buf && 33 == public_key.len) {
         memcpy(o->hdnode.public_key, public_key.buf, 33);
     } else {
-        explicit_bzero(o->hdnode.public_key, 33);
+        memzero(o->hdnode.public_key, 33);
     }
     o->hdnode.curve = curve;
 
@@ -120,7 +121,7 @@ STATIC mp_obj_t mod_trezorcrypto_HDNode_derive(mp_obj_t self, mp_obj_t index) {
     uint32_t fp = hdnode_fingerprint(&o->hdnode);
 
     if (!hdnode_private_ckd(&o->hdnode, i)) {
-        explicit_bzero(&o->hdnode, sizeof(o->hdnode));
+        memzero(&o->hdnode, sizeof(o->hdnode));
         mp_raise_ValueError("Failed to derive");
     }
     o->fingerprint = fp;
@@ -157,7 +158,7 @@ STATIC mp_obj_t mod_trezorcrypto_HDNode_derive_path(mp_obj_t self, mp_obj_t path
     if (!hdnode_private_ckd_cached(&o->hdnode, pints, plen, &o->fingerprint)) {
         // derivation failed, reset the state and raise
         o->fingerprint = 0;
-        explicit_bzero(&o->hdnode, sizeof(o->hdnode));
+        memzero(&o->hdnode, sizeof(o->hdnode));
         mp_raise_ValueError("Failed to derive path");
     }
 
diff --git a/embed/extmod/modtrezorcrypto/modtrezorcrypto-blake256.h b/embed/extmod/modtrezorcrypto/modtrezorcrypto-blake256.h
index e60668b05c..a0fe241608 100644
--- a/embed/extmod/modtrezorcrypto/modtrezorcrypto-blake256.h
+++ b/embed/extmod/modtrezorcrypto/modtrezorcrypto-blake256.h
@@ -8,6 +8,7 @@
 #include "py/objstr.h"
 
 #include "blake256.h"
+#include "memzero.h"
 
 /// class Blake256:
 ///     '''
@@ -68,7 +69,7 @@ STATIC MP_DEFINE_CONST_FUN_OBJ_1(mod_trezorcrypto_Blake256_digest_obj, mod_trezo
 
 STATIC mp_obj_t mod_trezorcrypto_Blake256___del__(mp_obj_t self) {
     mp_obj_Blake256_t *o = MP_OBJ_TO_PTR(self);
-    explicit_bzero(&(o->ctx), sizeof(BLAKE256_CTX));
+    memzero(&(o->ctx), sizeof(BLAKE256_CTX));
     return mp_const_none;
 }
 STATIC MP_DEFINE_CONST_FUN_OBJ_1(mod_trezorcrypto_Blake256___del___obj, mod_trezorcrypto_Blake256___del__);
diff --git a/embed/extmod/modtrezorcrypto/modtrezorcrypto-blake2b.h b/embed/extmod/modtrezorcrypto/modtrezorcrypto-blake2b.h
index fd02af69d7..bccb1b875a 100644
--- a/embed/extmod/modtrezorcrypto/modtrezorcrypto-blake2b.h
+++ b/embed/extmod/modtrezorcrypto/modtrezorcrypto-blake2b.h
@@ -8,6 +8,7 @@
 #include "py/objstr.h"
 
 #include "blake2b.h"
+#include "memzero.h"
 
 /// class Blake2b:
 ///     '''
@@ -75,7 +76,7 @@ STATIC MP_DEFINE_CONST_FUN_OBJ_1(mod_trezorcrypto_Blake2b_digest_obj, mod_trezor
 
 STATIC mp_obj_t mod_trezorcrypto_Blake2b___del__(mp_obj_t self) {
     mp_obj_Blake2b_t *o = MP_OBJ_TO_PTR(self);
-    explicit_bzero(&(o->ctx), sizeof(BLAKE2B_CTX));
+    memzero(&(o->ctx), sizeof(BLAKE2B_CTX));
     return mp_const_none;
 }
 STATIC MP_DEFINE_CONST_FUN_OBJ_1(mod_trezorcrypto_Blake2b___del___obj, mod_trezorcrypto_Blake2b___del__);
diff --git a/embed/extmod/modtrezorcrypto/modtrezorcrypto-blake2s.h b/embed/extmod/modtrezorcrypto/modtrezorcrypto-blake2s.h
index 2c277c716d..1b9a042514 100644
--- a/embed/extmod/modtrezorcrypto/modtrezorcrypto-blake2s.h
+++ b/embed/extmod/modtrezorcrypto/modtrezorcrypto-blake2s.h
@@ -8,6 +8,7 @@
 #include "py/objstr.h"
 
 #include "blake2s.h"
+#include "memzero.h"
 
 /// class Blake2s:
 ///     '''
@@ -75,7 +76,7 @@ STATIC MP_DEFINE_CONST_FUN_OBJ_1(mod_trezorcrypto_Blake2s_digest_obj, mod_trezor
 
 STATIC mp_obj_t mod_trezorcrypto_Blake2s___del__(mp_obj_t self) {
     mp_obj_Blake2s_t *o = MP_OBJ_TO_PTR(self);
-    explicit_bzero(&(o->ctx), sizeof(BLAKE2S_CTX));
+    memzero(&(o->ctx), sizeof(BLAKE2S_CTX));
     return mp_const_none;
 }
 STATIC MP_DEFINE_CONST_FUN_OBJ_1(mod_trezorcrypto_Blake2s___del___obj, mod_trezorcrypto_Blake2s___del__);
diff --git a/embed/extmod/modtrezorcrypto/modtrezorcrypto-chacha20poly1305.h b/embed/extmod/modtrezorcrypto/modtrezorcrypto-chacha20poly1305.h
index 2be22902be..891b7610d8 100644
--- a/embed/extmod/modtrezorcrypto/modtrezorcrypto-chacha20poly1305.h
+++ b/embed/extmod/modtrezorcrypto/modtrezorcrypto-chacha20poly1305.h
@@ -8,6 +8,7 @@
 #include "py/objstr.h"
 
 #include "chacha20poly1305/rfc7539.h"
+#include "memzero.h"
 
 /// class ChaCha20Poly1305:
 ///     '''
@@ -105,7 +106,7 @@ STATIC MP_DEFINE_CONST_FUN_OBJ_1(mod_trezorcrypto_ChaCha20Poly1305_finish_obj, m
 
 STATIC mp_obj_t mod_trezorcrypto_ChaCha20Poly1305___del__(mp_obj_t self) {
     mp_obj_ChaCha20Poly1305_t *o = MP_OBJ_TO_PTR(self);
-    explicit_bzero(&(o->ctx), sizeof(chacha20poly1305_ctx));
+    memzero(&(o->ctx), sizeof(chacha20poly1305_ctx));
     o->alen = 0;
     o->plen = 0;
     return mp_const_none;
diff --git a/embed/extmod/modtrezorcrypto/modtrezorcrypto-pbkdf2.h b/embed/extmod/modtrezorcrypto/modtrezorcrypto-pbkdf2.h
index 4c551fa3db..b529867745 100644
--- a/embed/extmod/modtrezorcrypto/modtrezorcrypto-pbkdf2.h
+++ b/embed/extmod/modtrezorcrypto/modtrezorcrypto-pbkdf2.h
@@ -8,6 +8,7 @@
 #include "py/objstr.h"
 
 #include "pbkdf2.h"
+#include "memzero.h"
 
 /// class Pbkdf2:
 ///     '''
@@ -111,8 +112,8 @@ STATIC MP_DEFINE_CONST_FUN_OBJ_1(mod_trezorcrypto_Pbkdf2_key_obj, mod_trezorcryp
 
 STATIC mp_obj_t mod_trezorcrypto_Pbkdf2___del__(mp_obj_t self) {
     mp_obj_Pbkdf2_t *o = MP_OBJ_TO_PTR(self);
-    explicit_bzero(&(o->ctx256), sizeof(PBKDF2_HMAC_SHA256_CTX));
-    explicit_bzero(&(o->ctx512), sizeof(PBKDF2_HMAC_SHA512_CTX));
+    memzero(&(o->ctx256), sizeof(PBKDF2_HMAC_SHA256_CTX));
+    memzero(&(o->ctx512), sizeof(PBKDF2_HMAC_SHA512_CTX));
     return mp_const_none;
 }
 STATIC MP_DEFINE_CONST_FUN_OBJ_1(mod_trezorcrypto_Pbkdf2___del___obj, mod_trezorcrypto_Pbkdf2___del__);
diff --git a/embed/extmod/modtrezorcrypto/modtrezorcrypto-ripemd160.h b/embed/extmod/modtrezorcrypto/modtrezorcrypto-ripemd160.h
index 5b54aca730..59418c78dc 100644
--- a/embed/extmod/modtrezorcrypto/modtrezorcrypto-ripemd160.h
+++ b/embed/extmod/modtrezorcrypto/modtrezorcrypto-ripemd160.h
@@ -8,6 +8,7 @@
 #include "py/objstr.h"
 
 #include "ripemd160.h"
+#include "memzero.h"
 
 /// class Ripemd160:
 ///     '''
@@ -68,7 +69,7 @@ STATIC MP_DEFINE_CONST_FUN_OBJ_1(mod_trezorcrypto_Ripemd160_digest_obj, mod_trez
 
 STATIC mp_obj_t mod_trezorcrypto_Ripemd160___del__(mp_obj_t self) {
     mp_obj_Ripemd160_t *o = MP_OBJ_TO_PTR(self);
-    explicit_bzero(&(o->ctx), sizeof(RIPEMD160_CTX));
+    memzero(&(o->ctx), sizeof(RIPEMD160_CTX));
     return mp_const_none;
 }
 STATIC MP_DEFINE_CONST_FUN_OBJ_1(mod_trezorcrypto_Ripemd160___del___obj, mod_trezorcrypto_Ripemd160___del__);
diff --git a/embed/extmod/modtrezorcrypto/modtrezorcrypto-sha1.h b/embed/extmod/modtrezorcrypto/modtrezorcrypto-sha1.h
index 49f51285c8..2824f5ade6 100644
--- a/embed/extmod/modtrezorcrypto/modtrezorcrypto-sha1.h
+++ b/embed/extmod/modtrezorcrypto/modtrezorcrypto-sha1.h
@@ -8,6 +8,7 @@
 #include "py/objstr.h"
 
 #include "sha2.h"
+#include "memzero.h"
 
 /// class Sha1:
 ///     '''
@@ -68,7 +69,7 @@ STATIC MP_DEFINE_CONST_FUN_OBJ_1(mod_trezorcrypto_Sha1_digest_obj, mod_trezorcry
 
 STATIC mp_obj_t mod_trezorcrypto_Sha1___del__(mp_obj_t self) {
     mp_obj_Sha1_t *o = MP_OBJ_TO_PTR(self);
-    explicit_bzero(&(o->ctx), sizeof(SHA1_CTX));
+    memzero(&(o->ctx), sizeof(SHA1_CTX));
     return mp_const_none;
 }
 STATIC MP_DEFINE_CONST_FUN_OBJ_1(mod_trezorcrypto_Sha1___del___obj, mod_trezorcrypto_Sha1___del__);
diff --git a/embed/extmod/modtrezorcrypto/modtrezorcrypto-sha256.h b/embed/extmod/modtrezorcrypto/modtrezorcrypto-sha256.h
index da26a63a98..c665e77684 100644
--- a/embed/extmod/modtrezorcrypto/modtrezorcrypto-sha256.h
+++ b/embed/extmod/modtrezorcrypto/modtrezorcrypto-sha256.h
@@ -8,6 +8,7 @@
 #include "py/objstr.h"
 
 #include "sha2.h"
+#include "memzero.h"
 
 /// class Sha256:
 ///     '''
@@ -68,7 +69,7 @@ STATIC MP_DEFINE_CONST_FUN_OBJ_1(mod_trezorcrypto_Sha256_digest_obj, mod_trezorc
 
 STATIC mp_obj_t mod_trezorcrypto_Sha256___del__(mp_obj_t self) {
     mp_obj_Sha256_t *o = MP_OBJ_TO_PTR(self);
-    explicit_bzero(&(o->ctx), sizeof(SHA256_CTX));
+    memzero(&(o->ctx), sizeof(SHA256_CTX));
     return mp_const_none;
 }
 STATIC MP_DEFINE_CONST_FUN_OBJ_1(mod_trezorcrypto_Sha256___del___obj, mod_trezorcrypto_Sha256___del__);
diff --git a/embed/extmod/modtrezorcrypto/modtrezorcrypto-sha3-256.h b/embed/extmod/modtrezorcrypto/modtrezorcrypto-sha3-256.h
index 92d92a7e29..6aad9b400e 100644
--- a/embed/extmod/modtrezorcrypto/modtrezorcrypto-sha3-256.h
+++ b/embed/extmod/modtrezorcrypto/modtrezorcrypto-sha3-256.h
@@ -8,6 +8,7 @@
 #include "py/objstr.h"
 
 #include "sha3.h"
+#include "memzero.h"
 
 /// class Sha3_256:
 ///     '''
@@ -72,7 +73,7 @@ STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(mod_trezorcrypto_Sha3_256_digest_obj,
 
 STATIC mp_obj_t mod_trezorcrypto_Sha3_256___del__(mp_obj_t self) {
     mp_obj_Sha3_256_t *o = MP_OBJ_TO_PTR(self);
-    explicit_bzero(&(o->ctx), sizeof(SHA3_CTX));
+    memzero(&(o->ctx), sizeof(SHA3_CTX));
     return mp_const_none;
 }
 STATIC MP_DEFINE_CONST_FUN_OBJ_1(mod_trezorcrypto_Sha3_256___del___obj, mod_trezorcrypto_Sha3_256___del__);
diff --git a/embed/extmod/modtrezorcrypto/modtrezorcrypto-sha3-512.h b/embed/extmod/modtrezorcrypto/modtrezorcrypto-sha3-512.h
index a0f366964e..28eb4bcb70 100644
--- a/embed/extmod/modtrezorcrypto/modtrezorcrypto-sha3-512.h
+++ b/embed/extmod/modtrezorcrypto/modtrezorcrypto-sha3-512.h
@@ -8,6 +8,7 @@
 #include "py/objstr.h"
 
 #include "sha3.h"
+#include "memzero.h"
 
 /// class Sha3_512:
 ///     '''
@@ -72,7 +73,7 @@ STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(mod_trezorcrypto_Sha3_512_digest_obj,
 
 STATIC mp_obj_t mod_trezorcrypto_Sha3_512___del__(mp_obj_t self) {
     mp_obj_Sha3_512_t *o = MP_OBJ_TO_PTR(self);
-    explicit_bzero(&(o->ctx), sizeof(SHA3_CTX));
+    memzero(&(o->ctx), sizeof(SHA3_CTX));
     return mp_const_none;
 }
 STATIC MP_DEFINE_CONST_FUN_OBJ_1(mod_trezorcrypto_Sha3_512___del___obj, mod_trezorcrypto_Sha3_512___del__);
diff --git a/embed/extmod/modtrezorcrypto/modtrezorcrypto-sha512.h b/embed/extmod/modtrezorcrypto/modtrezorcrypto-sha512.h
index 27ea40cd61..a6445aaeb2 100644
--- a/embed/extmod/modtrezorcrypto/modtrezorcrypto-sha512.h
+++ b/embed/extmod/modtrezorcrypto/modtrezorcrypto-sha512.h
@@ -8,6 +8,7 @@
 #include "py/objstr.h"
 
 #include "sha2.h"
+#include "memzero.h"
 
 /// class Sha512:
 ///     '''
@@ -67,7 +68,7 @@ STATIC MP_DEFINE_CONST_FUN_OBJ_1(mod_trezorcrypto_Sha512_digest_obj, mod_trezorc
 
 STATIC mp_obj_t mod_trezorcrypto_Sha512___del__(mp_obj_t self) {
     mp_obj_Sha512_t *o = MP_OBJ_TO_PTR(self);
-    explicit_bzero(&(o->ctx), sizeof(SHA512_CTX));
+    memzero(&(o->ctx), sizeof(SHA512_CTX));
     return mp_const_none;
 }
 STATIC MP_DEFINE_CONST_FUN_OBJ_1(mod_trezorcrypto_Sha512___del___obj, mod_trezorcrypto_Sha512___del__);
diff --git a/vendor/trezor-crypto b/vendor/trezor-crypto
index b7f73ee3ff..bb4c3d0525 160000
--- a/vendor/trezor-crypto
+++ b/vendor/trezor-crypto
@@ -1 +1 @@
-Subproject commit b7f73ee3ff78e09c266a30dbc31407558d471615
+Subproject commit bb4c3d052561bd31856a03d975ca226571f6a893