CVE-2025-67490
📋 TL;DR
The Auth0 Next.js SDK vulnerability allows simultaneous requests from the same client to cause improper token cache lookups, potentially leading to authentication failures or incorrect token handling. This affects Next.js applications using Auth0 SDK versions 4.11.0-4.11.2 and 4.12.0 for user authentication.
💻 Affected Systems
- Auth0 Next.js SDK
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Authentication failures causing user lockouts or incorrect authorization decisions, potentially allowing unauthorized access to protected resources.
Likely Case
Intermittent authentication failures or incorrect token responses during high-concurrency scenarios, disrupting user sessions.
If Mitigated
Minor performance degradation or occasional authentication hiccups that don't compromise security.
🎯 Exploit Status
Requires simultaneous requests from the same authenticated client to trigger the cache lookup issue.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 4.11.2 or 4.12.1
Vendor Advisory: https://github.com/auth0/nextjs-auth0/security/advisories/GHSA-wcgj-f865-c7j7
Restart Required: Yes
Instructions:
1. Update package.json to use @auth0/nextjs-auth0 version 4.11.2 or 4.12.1. 2. Run npm update @auth0/nextjs-auth0 or yarn upgrade @auth0/nextjs-auth0. 3. Restart your Next.js application server.
🔧 Temporary Workarounds
Rate limiting per client
allImplement client-side rate limiting to reduce simultaneous requests from the same user
Disable token caching temporarily
allConfigure the SDK to bypass TokenRequestCache for critical authentication flows
🧯 If You Can't Patch
- Implement additional authentication validation layers
- Monitor authentication logs for unusual patterns and implement alerting
🔍 How to Verify
Check if Vulnerable:
Check package.json for @auth0/nextjs-auth0 version: if version is 4.11.0, 4.11.1, 4.11.2, or 4.12.0, you are vulnerable.Check Version:
npm list @auth0/nextjs-auth0Verify Fix Applied:
Verify package.json shows @auth0/nextjs-auth0 version 4.11.2 or 4.12.1, then test concurrent authentication requests from the same user.📡 Detection & Monitoring
Log Indicators:
- Multiple authentication failures for same user within short timeframes
- Token validation errors with cache-related messages
Network Indicators:
- Unusual patterns of simultaneous authentication requests from single clients
SIEM Query:
source="auth0-logs" AND (error="token_cache" OR error="authentication_failure") | stats count by user_id