CVE-2025-30706
📋 TL;DR
This vulnerability in Oracle MySQL Connector/J allows attackers with low privileges and network access to potentially take over the connector software. It affects versions 9.0.0 through 9.2.0 of MySQL Connector/J. Successful exploitation could lead to complete compromise of the connector's functionality.
💻 Affected Systems
- Oracle MySQL Connector/J
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete takeover of MySQL Connector/J, allowing attackers to execute arbitrary code, access sensitive database credentials, and potentially pivot to the underlying database server.
Likely Case
Unauthorized access to database connections, credential theft, and potential data exfiltration through compromised connector instances.
If Mitigated
Limited impact due to network segmentation, proper privilege separation, and monitoring that would detect anomalous connector behavior.
🎯 Exploit Status
Requires low privileged attacker with network access via multiple protocols. Oracle describes it as 'difficult to exploit'.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 9.2.1 or later
Vendor Advisory: https://www.oracle.com/security-alerts/cpuapr2025.html
Restart Required: Yes
Instructions:
1. Download MySQL Connector/J 9.2.1 or later from Oracle's website. 2. Replace the vulnerable connector JAR file in your application's classpath. 3. Restart all applications using the connector. 4. Verify the new version is being used.
🔧 Temporary Workarounds
Network Segmentation
allRestrict network access to MySQL Connector/J instances to only trusted hosts and applications.
# Configure firewall rules to limit inbound connections to MySQL ports
# Example: iptables -A INPUT -p tcp --dport 3306 -s trusted_network -j ACCEPT
Least Privilege Database Accounts
allUse database accounts with minimal privileges required for application functionality.
# MySQL command to create limited privilege user:
CREATE USER 'appuser'@'localhost' IDENTIFIED BY 'password';
GRANT SELECT, INSERT, UPDATE, DELETE ON database.* TO 'appuser'@'localhost';
🧯 If You Can't Patch
- Implement strict network access controls to limit which systems can connect to MySQL connectors
- Monitor for unusual database connection patterns or unexpected connector behavior
🔍 How to Verify
Check if Vulnerable:
Check the version of mysql-connector-java.jar file in your application's classpath or dependencies. Versions 9.0.0 through 9.2.0 are vulnerable.Check Version:
java -cp mysql-connector-java.jar com.mysql.cj.jdbc.Driver | grep 'MySQL Connector/J' or check META-INF/MANIFEST.MF for Implementation-VersionVerify Fix Applied:
Verify the mysql-connector-java.jar file version is 9.2.1 or higher after replacement.📡 Detection & Monitoring
Log Indicators:
- Unusual database connection attempts from unexpected sources
- Multiple failed authentication attempts followed by successful connections
- Unexpected SQL queries or database operations
Network Indicators:
- Unusual traffic patterns to MySQL ports (default 3306) from unauthorized sources
- Multiple connection attempts from single source to different MySQL instances
SIEM Query:
source="mysql.log" AND ("Access denied" OR "Failed login") | stats count by src_ip dest_ip | where count > threshold