Cryptographic Issues Affecting elliptic package, versions <6.5.3

elliptic is a fast elliptic-curve cryptography implementation in plain javascript.

Affected versions of this package are vulnerable to Cryptographic Issues. Elliptic allows ECDSA signature malleability via variations in encoding, leading \0 bytes, or integer overflows. This could conceivably have a security-relevant impact if an application relied on a single canonical signature.

PoC

var crypto = require('crypto')
var EC = require('elliptic').ec;
var ec = new EC('secp256k1');

var obj = require("./poc_ecdsa_secp256k1_sha256_test.json");
for (let testGroup of obj.testGroups) {
var key = ec.keyFromPublic(testGroup.key.uncompressed, 'hex');

for(let test of testGroup.tests) {
 console.log("[*] Test " + test.tcId + " result: " + test.result)

 msgHash = crypto.createHash('sha256').update(Buffer.from(test.msg, 'hex')).digest();
 
 try {
  result = key.verify(msgHash, Buffer.from(test.sig, 'hex'));

 if (result == true) {
  if (test.result == "valid" || test.result == "acceptable")
   console.log("Result: PASS");
  else
   console.log("Result: FAIL")     
 }

 if (result == false) {
  if (test.result == "valid" || test.result == "acceptable")
   console.log("Result: FAIL");
  else
   console.log("Result: PASS")     
 }



 } catch (e) {
  console.log("ERROR - VERIFY: " + e)

  if (test.result == "valid" || test.result == "acceptable")
   console.log("Result: FAIL");
  else
   console.log("Result: PASS")     



 }


}

}

• Elliptic NPM Package
• GitHub Issue
• How Not To Use ECDSA
• Malleability Attack