CVE-2025-36071
📋 TL;DR
IBM Db2 database servers running vulnerable versions can crash when processing specially crafted queries due to improper memory resource release. This denial of service vulnerability affects Db2 11.5.0-11.5.9 and 12.1.0-12.1.2 on Linux, UNIX, and Windows systems, potentially disrupting database availability.
💻 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
Db2 by Ibm
Db2 by Ibm
Db2 by Ibm
⚠️ Risk & Real-World Impact
Worst Case
Complete database server crash leading to extended service outage, data unavailability, and potential cascading failures in dependent applications.
Likely Case
Intermittent database crashes requiring restart, causing temporary service disruption and potential data loss for in-flight transactions.
If Mitigated
Minimal impact with proper query validation, monitoring, and rapid restart capabilities in place.
🎯 Exploit Status
Requires ability to execute queries against the database, but no authentication bypass is indicated. Attackers need to craft specific queries to trigger the memory issue.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Apply fixes from IBM: 11.5.9.1 or later for 11.5.x, 12.1.2.1 or later for 12.1.x
Vendor Advisory: https://www.ibm.com/support/pages/node/7240955
Restart Required: Yes
Instructions:
1. Review IBM advisory for specific fix details. 2. Download appropriate fix pack from IBM Fix Central. 3. Apply fix following IBM Db2 installation procedures. 4. Restart Db2 instances to apply changes.
🔧 Temporary Workarounds
Query Input Validation
allImplement strict validation and sanitization of all query inputs to prevent malicious query execution.
Database Connection Restrictions
allLimit database connections to trusted applications and users only, reducing attack surface.
🧯 If You Can't Patch
- Implement network segmentation to restrict database access to only necessary applications
- Deploy monitoring for abnormal query patterns and database crash events
🔍 How to Verify
Check if Vulnerable:
Check Db2 version using 'db2level' command and compare against affected ranges: 11.5.0-11.5.9 or 12.1.0-12.1.2Check Version:
db2level | grep "Product name"Verify Fix Applied:
Verify version is updated to 11.5.9.1+ or 12.1.2.1+ using 'db2level' command📡 Detection & Monitoring
Log Indicators:
- Db2 instance crashes in db2diag.log
- Abnormal termination messages
- Memory allocation failures in logs
Network Indicators:
- Sudden loss of database connectivity
- Connection resets from database server
SIEM Query:
source="db2diag.log" AND ("crash" OR "abnormal termination" OR "memory allocation failed")