diff --git a/include/keepkey/transport/messages-tendermint.options b/include/keepkey/transport/messages-tendermint.options
index 8d071571..5fc137f0 100644
--- a/include/keepkey/transport/messages-tendermint.options
+++ b/include/keepkey/transport/messages-tendermint.options
@@ -1,22 +1,22 @@
 TendermintGetAddress.address_n                             max_count:10
-TendermintGetAddress.address_prefix                        max_size:10
-TendermintGetAddress.chain_name                            max_size:15
+TendermintGetAddress.address_prefix                        max_length:9
+TendermintGetAddress.chain_name                            max_length:14
 
-TendermintAddress.address                                  max_size:46
+TendermintAddress.address                                  max_length:53
 
-TendermintMsgAck.denom                                     max_size:10
-TendermintMsgAck.chain_name                                max_size:15
-TendermintMsgAck.message_type_prefix                       max_size:25
+TendermintMsgAck.denom                                     max_length:9
+TendermintMsgAck.chain_name                                max_length:14
+TendermintMsgAck.message_type_prefix                       max_length:24
 
 TendermintSignTx.address_n                                 max_count:10
-TendermintSignTx.chain_id                                  max_size:32
-TendermintSignTx.memo                                      max_size:256
-TendermintSignTx.denom                                     max_size:10
-TendermintSignTx.chain_name                                max_size:15
-TendermintSignTx.message_type_prefix                       max_size:25
+TendermintSignTx.chain_id                                  max_length:31
+TendermintSignTx.memo                                      max_length:255
+TendermintSignTx.denom                                     max_length:9
+TendermintSignTx.chain_name                                max_length:14
+TendermintSignTx.message_type_prefix                       max_length:24
 
-TendermintMsgSend.from_address                             max_size:46
-TendermintMsgSend.to_address                               max_size:46
+TendermintMsgSend.from_address                             max_length:53
+TendermintMsgSend.to_address                               max_length:53
 
 TendermintSignedTx.public_key                              max_size:33
 TendermintSignedTx.signature                               max_size:64
diff --git a/lib/firmware/fsm_msg_tendermint.h b/lib/firmware/fsm_msg_tendermint.h
index 30c8ef8a..53d0a2f5 100644
--- a/lib/firmware/fsm_msg_tendermint.h
+++ b/lib/firmware/fsm_msg_tendermint.h
@@ -112,9 +112,9 @@ void fsm_msgTendermintMsgAck(const TendermintMsgAck *msg) {
   CHECK_PARAM(tendermint_signingIsInited(), "Signing not in progress");
   if (!msg->has_send || !msg->send.has_to_address || !msg->send.has_amount) {
     tendermint_signAbort();
-    // 21 + ^15 + 1 = 37
+    // 8 + ^14 + 13 + 1 = 36
     char failmsg[40];
-    snprintf(failmsg, 40, "Invalid %s Message Type", msg->chain_name);
+    snprintf(failmsg, sizeof(failmsg), "Invalid %s Message Type", msg->chain_name);
 
     fsm_sendFailure(FailureType_Failure_FirmwareError,
                     _(failmsg));
diff --git a/lib/firmware/signtx_tendermint.c b/lib/firmware/signtx_tendermint.c
index e4cdaa46..a6baa433 100644
--- a/lib/firmware/signtx_tendermint.c
+++ b/lib/firmware/signtx_tendermint.c
@@ -59,10 +59,14 @@ bool tendermint_signTxInit(const HDNode *_node, const void *_msg, const size_t m
     return false;
   }
 
+  if (strnlen(denom, 10) > 9) {
+    return false;
+  }
+
   memcpy((void *)&tmsg, _msg, msgsize);
 
   bool success = true;
-  char buffer[64 + 1];
+  char buffer[128];
 
   sha256_Init(&ctx);
 
@@ -77,7 +81,7 @@ bool tendermint_signTxInit(const HDNode *_node, const void *_msg, const size_t m
   sha256_Update(&ctx, (uint8_t *)chainid_prefix, strlen(chainid_prefix));
   tendermint_sha256UpdateEscaped(&ctx, tmsg.chain_id, strlen(tmsg.chain_id));
 
-  // 30 + ^10 + 19 = ^59
+  // 30 + ^10 + 11 + ^9 + 3 = ^63
   success &=
       tendermint_snprintf(&ctx, buffer, sizeof(buffer),
                           "\",\"fee\":{\"amount\":[{\"amount\":\"%" PRIu32
@@ -103,7 +107,7 @@ bool tendermint_signTxInit(const HDNode *_node, const void *_msg, const size_t m
 
 bool tendermint_signTxUpdateMsgSend(const uint64_t amount, const char *to_address, const char *chainstr, 
                                     const char *denom, const char *msgTypePrefix) {
-  char buffer[64 + 1];
+  char buffer[128];
   size_t decoded_len;
   char hrp[45];
   uint8_t decoded[38];
@@ -112,7 +116,12 @@ bool tendermint_signTxUpdateMsgSend(const uint64_t amount, const char *to_addres
     return false;
   }
 
-  char from_address[46];
+  if (strnlen(msgTypePrefix, 25) > 24 || strnlen(denom, 10) > 9 || strnlen(chainstr, 15) > 14) {
+    return false;
+  }
+
+  // ^14 + 39 + 1 = ^54
+  char from_address[54];
   if (!tendermint_getAddress(&node, chainstr, from_address)) {
     return false;
   }
@@ -121,25 +130,21 @@ bool tendermint_signTxUpdateMsgSend(const uint64_t amount, const char *to_addres
     sha256_Update(&ctx, (uint8_t *)",", 1);
   }
 
-  if (strnlen(msgTypePrefix, 26) > 25 || strnlen(denom, 11) > 10 || strnlen(chainstr, 13) > 12) {
-    return false;
-  }
-
   bool success = true;
 
-  // 9 + ^25 + 19 = ^53
+  // 9 + ^24 + 19 = ^52
   success &= tendermint_snprintf(&ctx, buffer, sizeof(buffer), "{\"type\":\"%s/MsgSend\",\"value\":{", msgTypePrefix);
 
-  // 21 + ^20 + 19 = ^60
+  // 21 + ^20 + 11 + ^9 + 3 = ^64
   success &= tendermint_snprintf(
       &ctx, buffer, sizeof(buffer),
       "\"amount\":[{\"amount\":\"%" PRIu64 "\",\"denom\":\"%s\"}]", amount, denom);
 
-  // 17 + 45 + 1 = 63
+  // 17 + ^53 + 1 = ^71
   success &= tendermint_snprintf(&ctx, buffer, sizeof(buffer),
                                  ",\"from_address\":\"%s\"", from_address);
 
-  // 15 + 45 + 3 = 63
+  // 15 + ^53 + 3 = ^71
   success &= tendermint_snprintf(&ctx, buffer, sizeof(buffer),
                                  ",\"to_address\":\"%s\"}}", to_address);
 
@@ -149,9 +154,9 @@ bool tendermint_signTxUpdateMsgSend(const uint64_t amount, const char *to_addres
 }
 
 bool tendermint_signTxFinalize(uint8_t *public_key, uint8_t *signature) {
-  char buffer[64 + 1];
+  char buffer[128];
 
-  // 16 + ^20 = ^36
+  // 14 + ^20 + 2 = ^36
   if (!tendermint_snprintf(&ctx, buffer, sizeof(buffer),
                            "],\"sequence\":\"%" PRIu64 "\"}", tmsg.sequence))
     return false;