CVE-2024-51479
📋 TL;DR
This CVE describes an authorization bypass vulnerability in Next.js middleware. Attackers can bypass pathname-based authorization checks for pages directly under the application's root directory, potentially accessing restricted content. Only Next.js applications using middleware for authorization based on pathnames are affected.
💻 Affected Systems
- Next.js
📦 What is this software?
Next.js by Vercel
⚠️ Risk & Real-World Impact
Worst Case
Unauthorized users gain access to sensitive pages and data that should be protected by authorization middleware, potentially leading to data breaches or privilege escalation.
Likely Case
Attackers bypass authorization to access restricted pages or content that should only be available to authenticated/authorized users.
If Mitigated
If proper authentication is implemented at the application level (not just middleware) or if the application doesn't use pathname-based authorization in middleware, impact is minimal.
🎯 Exploit Status
Exploitation requires knowledge of application structure and affected paths. No public exploit code identified at this time.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 14.2.15 and later
Vendor Advisory: https://github.com/vercel/next.js/security/advisories/GHSA-7gfc-8cq8-jh5f
Restart Required: Yes
Instructions:
1. Update Next.js to version 14.2.15 or later using npm/yarn/pnpm. 2. Run 'npm update next' or 'yarn upgrade next' or 'pnpm update next'. 3. Restart your Next.js application. 4. Test authorization functionality.
🔧 Temporary Workarounds
No official workarounds
allThe vendor states there are no official workarounds for this vulnerability
🧯 If You Can't Patch
- Move authorization logic from middleware to individual page components or API routes
- Implement additional authentication checks at the application level beyond middleware
🔍 How to Verify
Check if Vulnerable:
Check if your Next.js application uses middleware for authorization based on pathnames and is version <14.2.15Check Version:
npm list next | grep next or check package.jsonVerify Fix Applied:
Verify Next.js version is 14.2.15 or later and test authorization functionality for pages directly under root directory📡 Detection & Monitoring
Log Indicators:
- Unauthorized access attempts to pages directly under root directory
- Successful access to protected pages without proper authentication logs
Network Indicators:
- HTTP requests to root-level pages that should be protected
- Unusual access patterns to /foo, /bar, etc. paths
SIEM Query:
web.access AND (path:"/foo" OR path:"/bar" OR path:"/[root-level-page]") AND NOT auth.success