CVE-2025-62228
📋 TL;DR
Apache Flink CDC 3.4.0 contains a SQL injection vulnerability that allows authenticated database users to execute arbitrary SQL commands by crafting malicious database or table names. This affects organizations using Flink CDC for change data capture with vulnerable configurations. The vulnerability requires database authentication but can lead to data manipulation or exfiltration.
💻 Affected Systems
- Apache Flink CDC
📦 What is this software?
Flink Cdc by Apache
⚠️ Risk & Real-World Impact
Worst Case
Authenticated attacker gains full database control, leading to data theft, corruption, or complete system compromise through privilege escalation.
Likely Case
Malicious insider or compromised account executes unauthorized SQL queries to access, modify, or delete sensitive data within their database permissions.
If Mitigated
Attack limited to database operations within the compromised user's existing permissions, with audit logging capturing suspicious activity.
🎯 Exploit Status
Requires authenticated database access but SQL injection techniques are well-understood and easily weaponized.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 3.5.0
Vendor Advisory: https://lists.apache.org/thread/3dn0hc1wbc5sj0jbgdg33gtnwlw7qrl3
Restart Required: Yes
Instructions:
1. Stop Flink CDC services. 2. Backup configurations and data. 3. Upgrade to Flink CDC 3.5.0. 4. Restart services. 5. Verify functionality.
🔧 Temporary Workarounds
Input Validation
allImplement strict input validation for database and table names to reject suspicious characters.
# Configure application to validate identifiers against whitelist patterns
# Example regex: ^[a-zA-Z0-9_]+$
Database Permission Reduction
allLimit database user permissions to minimum required operations.
# Database-specific commands to revoke unnecessary privileges
# Example PostgreSQL: REVOKE ALL ON DATABASE dbname FROM username;
🧯 If You Can't Patch
- Implement network segmentation to isolate Flink CDC from sensitive databases
- Enable comprehensive SQL query logging and monitoring for injection patterns
🔍 How to Verify
Check if Vulnerable:
Check Flink CDC version: if version is exactly 3.4.0 and uses database operations with user-controlled identifiers.Check Version:
flink-cdc --version or check pom.xml for versionVerify Fix Applied:
Confirm version is 3.5.0 or higher and test with crafted identifiers that previously triggered injection.📡 Detection & Monitoring
Log Indicators:
- Unusual SQL queries with concatenated strings
- Database errors containing user-supplied identifiers
- Multiple failed login attempts followed by complex queries
Network Indicators:
- Unusual database connection patterns from Flink CDC hosts
- Large data transfers from databases
SIEM Query:
source="flink-cdc" AND (query="UNION" OR query="SELECT * FROM" OR query CONTAINS special characters)