CVE-2020-4701
📋 TL;DR
CVE-2020-4701 is a buffer overflow vulnerability in IBM DB2 that allows a local attacker to execute arbitrary code with root privileges. This affects DB2 versions 10.5, 11.1, and 11.5 on Linux, UNIX, and Windows systems. Attackers with local access can potentially gain complete control of the database server.
💻 Affected Systems
- IBM DB2 for Linux, UNIX and Windows
- IBM DB2 Connect Server
📦 What is this software?
Db2 by Ibm
Db2 by Ibm
Db2 by Ibm
⚠️ Risk & Real-World Impact
Worst Case
Local attacker gains root privileges and executes arbitrary code, leading to complete system compromise, data theft, and lateral movement.
Likely Case
Privileged database user or attacker with local access escalates to root and compromises the DB2 instance and underlying OS.
If Mitigated
With proper access controls and patching, impact is limited to denial of service at most.
🎯 Exploit Status
Requires local access and knowledge of buffer overflow exploitation. No public exploit code available.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Apply fixes from IBM Security Bulletin: 10.5 FP11, 11.1.4.6, 11.5.6.0 or later
Vendor Advisory: https://www.ibm.com/support/pages/node/6370025
Restart Required: Yes
Instructions:
1. Download appropriate fix pack from IBM Fix Central. 2. Stop all DB2 services. 3. Apply fix pack according to IBM documentation. 4. Restart DB2 services. 5. Verify installation.
🔧 Temporary Workarounds
Restrict Local Access
allLimit local login access to DB2 servers to authorized administrators only
# Use OS-level access controls
# Example: Restrict SSH/shell access via /etc/ssh/sshd_config
# Example: Use sudo policies to limit privilege escalation
Principle of Least Privilege
linuxEnsure DB2 runs with minimal necessary privileges, not as root where possible
# Review and adjust DB2 instance owner privileges
# Consider running DB2 under non-root service account
🧯 If You Can't Patch
- Implement strict access controls to limit who can log into DB2 servers locally
- Monitor for suspicious local activity and privilege escalation attempts
🔍 How to Verify
Check if Vulnerable:
Check DB2 version: db2level command. If version is 10.5, 11.1, or 11.5 without patches, system is vulnerable.Check Version:
db2level | grep 'Product is installed at'Verify Fix Applied:
Verify version is patched: db2level should show 10.5 FP11, 11.1.4.6, 11.5.6.0 or later.📡 Detection & Monitoring
Log Indicators:
- Unexpected local process execution with elevated privileges
- DB2 service crashes or abnormal termination
- Suspicious local user activity on DB2 servers
Network Indicators:
- None - local exploit only
SIEM Query:
Process creation where parent process is DB2-related and privilege level changes to root/SYSTEM