CVE-2023-4316
📋 TL;DR
Zod versions 3.21.0 through 3.22.3 contain a vulnerability where attackers can cause denial of service by sending specially crafted email addresses during validation. This affects any application using Zod for email validation, particularly web applications and APIs that process user input.
💻 Affected Systems
- Zod
📦 What is this software?
Zod by Zod
⚠️ Risk & Real-World Impact
Worst Case
Complete service unavailability due to resource exhaustion, potentially affecting all users of the vulnerable application.
Likely Case
Degraded performance or temporary service disruption for specific endpoints that validate email addresses.
If Mitigated
Minimal impact with proper input validation and rate limiting in place.
🎯 Exploit Status
Exploitation requires sending malicious email addresses to validation endpoints. No authentication needed if endpoints are public.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 3.22.4
Vendor Advisory: https://www.npmjs.com/package/zod
Restart Required: No
Instructions:
1. Update Zod package: npm update zod
2. Verify version: npm list zod
3. Test email validation functionality
🔧 Temporary Workarounds
Input Sanitization
allImplement custom email validation or sanitization before passing to Zod
Rate Limiting
allImplement rate limiting on email validation endpoints
🧯 If You Can't Patch
- Disable email validation functionality if not critical
- Implement WAF rules to block suspicious email patterns
🔍 How to Verify
Check if Vulnerable:
Check package.json or run: npm list zod | grep zodCheck Version:
npm list zod | grep zodVerify Fix Applied:
Confirm installed version is 3.22.4 or higher: npm list zod📡 Detection & Monitoring
Log Indicators:
- Unusually long email addresses in validation logs
- High CPU/memory usage on validation endpoints
- Increased error rates on email validation
Network Indicators:
- Multiple requests with malformed email addresses from single IP
- Unusual patterns in email validation API calls
SIEM Query:
source="application_logs" AND ("email validation" OR "zod") AND (error OR timeout OR "high resource")