CVE-2025-0915 Overview
IBM Db2 for Linux, UNIX, and Windows (including DB2 Connect Server) contains a memory resource management vulnerability that could allow an authenticated user to cause a denial of service condition. The vulnerability exists due to insufficient release of allocated memory resources under specific configurations, potentially leading to service degradation or complete unavailability of the database system.
Critical Impact
Authenticated attackers can exploit this memory leak vulnerability to exhaust system resources, causing denial of service to IBM Db2 database instances and impacting all dependent applications and services.
Affected Products
- IBM Db2 for Linux, UNIX and Windows 11.5.0 through 11.5.9
- IBM Db2 for Linux, UNIX and Windows 12.1.0 through 12.1.1
- DB2 Connect Server (all affected versions)
Discovery Timeline
- 2025-05-05 - CVE-2025-0915 published to NVD
- 2025-11-03 - Last updated in NVD database
Technical Details for CVE-2025-0915
Vulnerability Analysis
This vulnerability is classified as CWE-770 (Allocation of Resources Without Limits or Throttling). The flaw resides in how IBM Db2 manages memory allocation during specific database operations. Under certain configurations, allocated memory is not properly released after use, leading to a gradual accumulation of unreleased memory blocks.
The network-accessible nature of this vulnerability allows remote authenticated users to trigger the memory leak condition. While the attack requires low privileges, no user interaction is necessary for exploitation. The impact is limited to availability—there is no compromise of data confidentiality or integrity.
Root Cause
The root cause stems from improper memory management within IBM Db2's resource handling routines. When certain database operations are performed under specific configurations, the memory deallocation routines fail to properly release allocated memory blocks. This resource leak accumulates over time or through repeated exploitation, eventually exhausting available system memory and causing the database service to become unresponsive or crash.
Attack Vector
The attack vector is network-based, requiring the attacker to have authenticated access to the IBM Db2 database instance. The exploitation process involves:
- An authenticated user establishes a connection to the vulnerable Db2 instance
- The attacker performs specific database operations that trigger the memory allocation flaw
- Memory is allocated but not properly freed after the operation completes
- Repeated exploitation causes memory exhaustion
- The database service becomes unresponsive, resulting in denial of service
The vulnerability can be exploited remotely without user interaction, making it particularly concerning for internet-facing database deployments. For detailed technical information, refer to the IBM Security Advisory.
Detection Methods for CVE-2025-0915
Indicators of Compromise
- Abnormal memory consumption patterns on systems running IBM Db2
- Gradual increase in memory usage that does not stabilize or decrease over time
- Database connection timeouts or failures coinciding with high memory utilization
- System logs indicating memory allocation failures or out-of-memory conditions
Detection Strategies
- Monitor IBM Db2 memory utilization metrics for anomalous growth patterns
- Implement alerting for memory threshold breaches on database servers
- Review database audit logs for unusual patterns of repeated operations from specific users
- Deploy database activity monitoring to identify potential exploitation attempts
Monitoring Recommendations
- Establish baseline memory consumption metrics for Db2 instances under normal operation
- Configure system-level monitoring to alert on sustained memory growth exceeding established thresholds
- Monitor for repeated failed connection attempts that may indicate DoS attack in progress
- Review Db2 diagnostic logs (db2diag.log) for memory-related warnings or errors
How to Mitigate CVE-2025-0915
Immediate Actions Required
- Apply the latest security patches from IBM as outlined in the official security bulletin
- Review and restrict database access to only required authenticated users
- Implement connection rate limiting where possible to reduce exploitation potential
- Monitor affected systems closely for signs of exploitation until patches are applied
Patch Information
IBM has released security updates to address this vulnerability. Administrators should upgrade to patched versions of IBM Db2 as specified in the IBM Support Page. Additional advisory information is available from NetApp Security Advisory.
Priority should be given to patching production database systems, especially those accessible from untrusted networks. Review the IBM security bulletin for specific version requirements and upgrade paths.
Workarounds
- Restrict network access to Db2 instances using firewall rules to limit exposure
- Review and minimize the number of authenticated users with database access
- Implement resource monitoring with automatic service restart capabilities as a temporary measure
- Consider isolating affected Db2 instances until patches can be applied
# Example: Restrict Db2 listener to specific trusted networks
# Modify db2comm registry variable and firewall rules
db2set DB2COMM=TCPIP
# Configure firewall to limit access to Db2 port (default 50000)
iptables -A INPUT -p tcp --dport 50000 -s 10.0.0.0/8 -j ACCEPT
iptables -A INPUT -p tcp --dport 50000 -j DROP
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
