CVE-2023-30991
📋 TL;DR
IBM Db2 for Linux, UNIX and Windows (including Db2 Connect Server) versions 11.1 and 11.5 are vulnerable to denial of service attacks when processing specially crafted queries. This vulnerability allows attackers to crash the database service, disrupting availability for legitimate users. Organizations running affected Db2 versions on any supported operating system are at risk.
💻 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
Db2 by Ibm
Db2 by Ibm
⚠️ Risk & Real-World Impact
Worst Case
Complete database service outage leading to extended downtime, data unavailability, and business disruption.
Likely Case
Service crashes requiring manual restart, causing temporary unavailability and potential data loss in transactions.
If Mitigated
Minimal impact with proper network segmentation and query validation in place.
🎯 Exploit Status
Exploitation requires ability to execute queries against the database, typically requiring valid database credentials.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Apply fixes as specified in IBM advisory - see vendor advisory for specific fix packs.
Vendor Advisory: https://www.ibm.com/support/pages/node/7047499
Restart Required: Yes
Instructions:
1. Review IBM advisory for specific fix packs. 2. Apply appropriate fix pack for your Db2 version. 3. Restart Db2 services. 4. Verify patch application.
🔧 Temporary Workarounds
Network Access Control
allRestrict database access to only trusted applications and users.
Configure firewall rules to limit Db2 port access (default 50000/50001)
Query Monitoring
allImplement query monitoring and rate limiting to detect anomalous queries.
Configure Db2 audit policies for query monitoring
🧯 If You Can't Patch
- Implement strict network segmentation and firewall rules to limit database access.
- Deploy database activity monitoring to detect and alert on suspicious query patterns.
🔍 How to Verify
Check if Vulnerable:
Check Db2 version using 'db2level' command and compare against affected versions (11.1.x, 11.5.x).Check Version:
db2levelVerify Fix Applied:
Verify applied fix pack version matches or exceeds the patched version specified in IBM advisory.📡 Detection & Monitoring
Log Indicators:
- Unexpected service crashes
- Abnormal query patterns
- Connection spikes followed by service failure
Network Indicators:
- Multiple failed connection attempts to Db2 ports
- Unusual query traffic patterns
SIEM Query:
source="db2" AND (event_type="crash" OR event_type="service_stop")🔗 References
- https://exchange.xforce.ibmcloud.com/vulnerabilities/254037
- https://security.netapp.com/advisory/ntap-20231116-0005/
- https://www.ibm.com/support/pages/node/7047499
- https://exchange.xforce.ibmcloud.com/vulnerabilities/254037
- https://security.netapp.com/advisory/ntap-20231116-0005/
- https://www.ibm.com/support/pages/node/7047499
