CVE-2025-36424 Overview
IBM Db2 for Linux, UNIX and Windows (includes Db2 Connect Server) contains a vulnerability that could allow an authenticated user to cause a denial of service condition. The vulnerability stems from improper neutralization of special elements in data query logic, which can be exploited to disrupt database availability.
Critical Impact
Authenticated attackers can exploit improper input handling in data query logic to cause denial of service, potentially disrupting critical database operations and business continuity.
Affected Products
- IBM Db2 for Linux
- IBM Db2 for UNIX
- IBM Db2 for Windows (includes Db2 Connect Server)
Discovery Timeline
- 2026-01-30 - CVE CVE-2025-36424 published to NVD
- 2026-02-04 - Last updated in NVD database
Technical Details for CVE-2025-36424
Vulnerability Analysis
This vulnerability is classified under CWE-1284 (Improper Validation of Specified Quantity in Input), indicating that the IBM Db2 database engine fails to properly validate or neutralize special elements within data query logic. When a user submits specially crafted queries containing malicious input patterns, the database server does not adequately sanitize or handle these elements, leading to resource exhaustion or crash conditions.
The attack can be executed over the network by authenticated users with low privileges, requiring no user interaction. While the vulnerability does not compromise data confidentiality or integrity, it can severely impact system availability by causing the Db2 service to become unresponsive or crash entirely.
Root Cause
The root cause lies in the improper neutralization of special elements within the query processing logic of IBM Db2. The database engine fails to adequately validate input parameters in data queries, allowing malformed or specially crafted query elements to bypass normal processing safeguards. This deficiency in input validation enables attackers to trigger conditions that exhaust system resources or cause the database service to enter an unstable state.
Attack Vector
The vulnerability is exploitable remotely over the network by authenticated users. An attacker with valid database credentials can craft malicious queries containing special elements that are not properly neutralized by the query parser. When these queries are processed, they can trigger denial of service conditions.
The attack requires:
- Network access to the IBM Db2 server
- Valid authentication credentials (low privilege level sufficient)
- Knowledge of the query structure needed to trigger the vulnerability
No user interaction is required, and the scope remains unchanged, meaning the impact is limited to the vulnerable Db2 component itself.
Detection Methods for CVE-2025-36424
Indicators of Compromise
- Unusual database query patterns containing special characters or escape sequences
- Repeated database service crashes or restarts without clear operational cause
- Abnormal resource consumption (CPU, memory) during query processing
- Authentication logs showing repeated connections from suspicious sources followed by service disruptions
Detection Strategies
- Monitor database logs for query parsing errors or exceptions related to special character handling
- Implement anomaly detection for unusual query patterns from authenticated users
- Configure alerting for unexpected Db2 service restarts or availability issues
- Review audit logs for queries with abnormal character sequences or malformed syntax
Monitoring Recommendations
- Enable detailed query logging to capture potentially malicious query attempts
- Set up real-time monitoring for Db2 service health and availability metrics
- Implement rate limiting and anomaly detection for database query submissions
- Configure automated alerts for service disruption events correlated with specific user sessions
How to Mitigate CVE-2025-36424
Immediate Actions Required
- Review the IBM Support Page for specific patch and remediation guidance
- Apply available security updates from IBM as soon as possible
- Audit user accounts with database access and remove unnecessary privileges
- Implement network segmentation to limit exposure of Db2 services
- Enable enhanced logging to detect potential exploitation attempts
Patch Information
IBM has released security guidance for this vulnerability. Organizations should consult the official IBM Support Page for detailed patch information, affected version numbers, and specific remediation steps. Apply the recommended security updates according to your change management procedures.
Workarounds
- Restrict network access to Db2 services to only trusted IP ranges and VPN connections
- Implement additional input validation at the application layer before queries reach the database
- Review and minimize user privileges, applying the principle of least privilege
- Consider deploying a Web Application Firewall (WAF) or database firewall to filter malicious query patterns
- Monitor for and block suspicious query patterns at the network level while awaiting patch deployment
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
