message: Do not try to sign single sig taint inputs
  Reviewers: tyler, bigly
  Subscribers: tyler
diff: @@ -640,6 +640,11 @@ class AbstractUtxoCoin extends BaseCoin {
  for (let index = 0; index < transaction.ins.length; ++index) {
  debug('Signing input %d of %d', index + 1, transaction.ins.length);
  const currentUnspent = txPrebuild.txInfo.unspents[index];
  + // FIXME: this is a hack, is there a better way to do this?
  + if (_.isUndefined(currentUnspent.index)) {
  + debug('Skipping tainted input %d of %d', index + 1, transaction.ins.length);
  + continue;
  + }
  const path = 'm/0/0/' + currentUnspent.chain + '/' + currentUnspent.index;
  const privKey = hdPath.deriveKey(path);
  privKey.network = this.network;
  