CVE-2025-36425: 
IBM Db2 vulnerability analysis and mitigation

CVE-2025-36425 is a plaintext password storage vulnerability (CWE-256) in IBM Db2 for Linux, UNIX, and Windows (including Db2 Connect Server) that allows an authenticated user to obtain sensitive information under specific High Availability Disaster Recovery (HADR) configurations. Affected versions include 11.5.0 through 11.5.9 and 12.1.0 through 12.1.3 across Linux, UNIX, and Windows platforms. The vulnerability was published on February 17, 2026, with a patch made available around the same time. It carries a CVSS v3.1 base score of 6.5 (Medium) (Red Hat CVE, IBM Support).

The root cause is classified as CWE-256 (Plaintext Storage of a Password), meaning that under specific HADR configuration scenarios, IBM Db2 stores or exposes passwords in an unencrypted form that an authenticated user can access. The attack vector is network-based, requires low privileges, and has low attack complexity with no user interaction needed. The vulnerability is conditional on a specific HADR deployment configuration being present, which limits the attack surface to environments using that high-availability feature (Red Hat CVE, IBM Support).

Successful exploitation allows an authenticated low-privileged attacker to access sensitive plaintext credentials stored or exposed within the Db2 system under vulnerable HADR configurations. The primary impact is a high confidentiality breach — exposed credentials could enable further unauthorized access to database resources, lateral movement within the environment, or escalation of privileges. Integrity and availability are not directly impacted by this vulnerability (Red Hat CVE).

IBM has released a patch addressing this vulnerability; administrators should upgrade IBM Db2 11.5.x installations beyond version 11.5.9 and IBM Db2 12.1.x installations beyond version 12.1.3. Patch details and installation instructions are available via IBM's support portal. As interim measures, organizations should review and restrict HADR configurations to minimize exposure, limit the number of authenticated users with access to affected systems, and monitor database access logs for suspicious activity from authenticated accounts (IBM Support).