fix: the password hashing implementation uses scrypt... in...

[anupamme]

Summary

Fix high severity security issue in server/auth/users-store.js.

Vulnerability

Field	Value
ID	V-001
Severity	HIGH
Scanner	multi_agent_ai
Rule	V-001
File	server/auth/users-store.js:49
Assessment	Likely exploitable
Chain Complexity	2-step

Description: The password hashing implementation uses scrypt with N=16384 (2^14), which is below the recommended minimum of 2^15 (32768) iterations. This makes offline brute-force attacks significantly easier if an attacker obtains the password database through a data breach.

Evidence

Exploitation scenario: An attacker who obtains the password database can perform offline brute-force attacks with reduced computational cost.

Scanner confirmation: multi_agent_ai rule V-001 flagged this pattern.

Production code: This file is in the production codebase, not test-only code.

Threat Model Context

This is a web service - vulnerabilities in request handlers are directly exploitable by remote attackers.

Changes

• server/auth/users-store.js

Behavior Preservation

The change is scoped to 1 file on the vulnerable path; it only tightens handling of untrusted input and leaves valid inputs unaffected.

Security Invariant

Property: The security boundary is maintained under adversarial input

Regression test

import { describe, test, expect } from 'vitest';
import { hashPassword } from './server/auth/users-store.js';

describe("password hashing uses sufficient scrypt iterations (N >= 32768)", () => {
  const passwords = [
    "weak",           // weak password - should still have strong KDF
    "a".repeat(1000), // boundary: long password
    "ValidP@ss123",   // valid input
  ];

  test.each(passwords)("hashes password '%s' with adequate iterations", (password) => {
    const hash = hashPassword(password);
    const parts = hash.split('$');
    expect(parts[0]).toBe('scrypt');
    const N = parseInt(parts[1], 10);
    expect(N).toBeGreaterThanOrEqual(32768);
  });
});

This test guards against regressions — it's useful independent of the code change above.

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Automated security fix by OrbisAI Security