Vulnerability. This project uses empty key pairs. about crystals-kyber-ts HOT 13 CLOSED

Hello.

With all due respect, it does work. It's even been reviewed by the authors of the algorithm itself.

I'm not sure how you are using it, but the tests give you good examples on its proper usage.

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Explain then why the key pair is empty and generateKyberKeys is not used anywhere?

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from crystals-kyber-ts.

https://github.com/fisherstevenk/crystals-kyber-ts/tree/main/tests

from crystals-kyber-ts.

In your implementation, only KyberHandshake is publicly available, which does not have a key generation method, and does not call this generation internally. What you wrote in your tests cannot be repeated without importing KyberService. And in the example in readme.md, you only mention KyberHandshake, as if implying that it will generate the keys itself.

from crystals-kyber-ts.

import { Kyber1024Handshake } from "crystals-kyber-ts";

const bobHandshake = new Kyber1024Handshake();
const aliceHandshake = new Kyber1024Handshake();


const bobPublicKey: number[] = bobHandshake.publicKey;

//Prints 0 0 because key pair is not generated
console.log(bobPublicKey.length, bobHandshake.privateKey.length);
const aliceCipherText: number[] = aliceHandshake.generateCipherTextAndSharedSecret(bobPublicKey);

const bobSharedSecret: number[] = bobHandshake.generateRemoteSharedSecret(aliceCipherText);

from crystals-kyber-ts.

You can also assume that when you call generateCipherTextAndSharedSecret, a key pair will be generated, but no, you just run an empty key through SHA3 and get the hash a7ffc6f8bf1ed76651c14756a061d662f580ff4de43b49fa82d80a4b80f8434a which corresponds to an empty string.
kyber-handshake.ts:

kyber.service.ts:

Debugging the code from the previous comment:

SHA3-256 online:

from crystals-kyber-ts.

import { Kyber1024Handshake } from "crystals-kyber-ts";

const bobHandshake = new Kyber1024Handshake();
const aliceHandshake = new Kyber1024Handshake();
const chuckHandshake = new Kyber1024Handshake();


const bobPublicKey: number[] = bobHandshake.publicKey;

const aliceCipherText: number[] = aliceHandshake.generateCipherTextAndSharedSecret(bobPublicKey);

const bobSharedSecret: number[] = bobHandshake.generateRemoteSharedSecret(aliceCipherText);
const chuckSharedSecret: number[] = chuckHandshake.generateRemoteSharedSecret(aliceCipherText);
//Vulnerability! Chuck, having only the public aliceCipherText in his hands, can read all the correspondence!
console.log(Buffer.from(bobSharedSecret).equals(Buffer.from(chuckSharedSecret))); //prints true because keys is empty

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You should have the keys generated inside KyberHandshake automatically. It is also worth adding a key length check to KyberService.

from crystals-kyber-ts.

I'm sorry. I understand what you're saying now.

I will have an update for this soon, plus a working example repo.

Thank you.

from crystals-kyber-ts.

v1.0.3 will automatically create the public and private keys when you create a new KyberHandshake.

https://www.npmjs.com/package/crystals-kyber-ts

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That's better. Thanks for the quick fix!

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Thank you for your persistence and patience.

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