CVE-2024-21632

What is this vulnerability?

CVE-2024-21632 is categorized as a high Improper Authentication flaw with a CVSS base score of 8.6. Based on our vulnerability intelligence, this issue occurs when the application fails to securely handle untrusted data boundaries.

omniauth-microsoft_graph provides an Omniauth strategy for the Microsoft Graph API. Prior to versions 2.0.0, the implementation did not validate the legitimacy of the email attribute of the user nor did it give/document an option to do so, making it susceptible to nOAuth misconfiguration in cases when the email is used as a trusted user identifier. This could lead to account takeover. Version 2.0.0 contains a fix for this issue.

This architectural defect enables adversaries to bypass intended security controls, directly manipulating the application's execution state or data layer. Immediate strategic intervention is required.

Risk Assessment

Impact on Systems

✅ Unauthorized Data Access: Attackers can bypass authorization controls to access other users' data or administrative endpoints.

✅ Account Takeover: Broken authentication or authorization may enable full account compromise without valid credentials.

✅ API Abuse: Exploiting this vulnerability enables mass data harvesting or destructive operations through unprotected API endpoints.

How to Fix and Mitigate CVE-2024-21632

1. Apply Vendor Patches: Upgrade affected components to their latest, non-vulnerable versions immediately.
2. Implement Input Validation: Ensure all user-supplied data is validated, sanitized, and type-checked before processing.
3. Deploy Runtime Protection: Use Precogs continuous monitoring to detect exploitation attempts in real time.
4. Audit Dependencies: Review and update all third-party libraries and transitive dependencies.

Defending with Precogs AI

The omniauth-microsoft_graph strategy for Ruby contains an authentication bypass vulnerability. Attackers manipulate the OAuth callback response to impersonate arbitrary users, as the application fails to properly validate the token's cryptographic signature or audience. Precogs API Security Engine comprehensively audits cryptographic validation in identity tokens.

Use Precogs to continuously scan your codebase, binaries, APIs, and infrastructure for this vulnerability class and related attack patterns. Our AI-powered detection engine combines static analysis with threat intelligence to identify exploitable weaknesses before attackers do.

Start scanning with Precogs →

Vulnerability Code Signature

Attack Data Flow

Vulnerable Code Pattern

// ❌ VULNERABLE: Improper Authentication
app.post('/login', (req, res) => {
  const { username, password } = req.body;
  // Taint sink: weak or bypassable validation
  if (username === 'admin' || password === 'secret') {
    req.session.authenticated = true;
    res.send('Logged in');
  }
});

Secure Code Pattern

// ✅ SECURE: Robust Authentication
const bcrypt = require('bcrypt');
app.post('/login', async (req, res) => {
  const { username, password } = req.body;
  const user = await db.getUser(username);
  // Sanitized validation: secure password comparison
  if (user && await bcrypt.compare(password, user.passwordHash)) {
    req.session.authenticated = true;
    res.send('Logged in');
  } else {
    res.status(401).send('Invalid credentials');
  }
});

How Precogs Detects This

Precogs API Security Engine comprehensively audits endpoints to ensure strict authentication boundaries and secure logic.\n