2 files changed, 12 insertions, 0 deletions
diff --git a/ui/app/send.js b/ui/app/send.js
index 97ed29e4a..d28a6433b 100644
--- a/ui/app/send.js
+++ b/ui/app/send.js
@@ -7,6 +7,7 @@ const actions = require('./actions')
 const util = require('./util')
 const numericBalance = require('./util').numericBalance
 const addressSummary = require('./util').addressSummary
+const isHex = require('./util').isHex
 const EthBalance = require('./components/eth-balance')
 const ethUtil = require('ethereumjs-util')
 const RangeSlider = require('./components/range-slider')
@@ -312,6 +313,11 @@ SendTransactionScreen.prototype.onSubmit = function (gasPrice) {
     return this.props.dispatch(actions.displayWarning(message))
   }
 
+  if (!isHex(ethUtil.stripHexPrefix(txData)) && txData) {
+    message = 'Transaction data must be hex string.'
+    return this.props.dispatch(actions.displayWarning(message))
+  }
+
   this.props.dispatch(actions.hideWarning())
 
   var txParams = {
diff --git a/ui/app/util.js b/ui/app/util.js
index e4b77e2bc..facaef3ee 100644
--- a/ui/app/util.js
+++ b/ui/app/util.js
@@ -35,6 +35,7 @@ module.exports = {
   normalizeNumberToWei: normalizeNumberToWei,
   valueTable: valueTable,
   bnTable: bnTable,
+  isHex: isHex,
 }
 
 function valuesFor (obj) {
@@ -209,3 +210,8 @@ function readableDate (ms) {
   var time = `${hours}:${minutes.substr(-2)}:${seconds.substr(-2)}`
   return `${dateStr} ${time}`
 }
+
+function isHex (str) {
+  if (str.match(/[g-zG-Z]/) || str.match(/\W/)) return false
+  return true
+}