Channel.prototype.close = function() {
  var ret = true;
  var outgoing = this.outgoing;

  if (outgoing.state === 'open' || outgoing.state === 'eof') {
    outgoing.state = 'closing';
    ret = this._client._sshstream.channelClose(outgoing.id);
  }

  return ret;
};
The software constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command when it is sent to a downstream component.