CVE-2026-87958 in Db2
Summary
by MITRE • 09/10/2026
IBM Db2 11.5.0 through 11.5.9, and 12.1.0 through 12.1.5 is vulnerable to a denial of service where a specific functionality on a Db2 server can be disabled by a privileged user under certain conditions.
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Analysis
by VulDB Data Team • 09/10/2026
The vulnerability identified in IBM Db2 versions 11.5.0 through 11.5.9 and 12.1.0 through 12.1.5 represents a significant risk to database availability, classified as a denial of service condition resulting from improper internal state management or resource handling within the server architecture. Unlike typical external attacks that exploit unauthenticated access vectors, this specific flaw requires authentication with privileged user credentials, indicating an insider threat scenario or a compromise of administrative accounts rather than a remote code execution vector for unauthorized actors. The core technical issue lies in a specific functionality where certain operational commands or internal processes can be triggered by these elevated users to disable critical server components or services. This behavior suggests that the software fails to adequately validate the context, scope, or side effects of privileged operations, allowing an actor with high-level access to inadvertently or maliciously disrupt the database engine's ability to function correctly.
From a technical perspective, this vulnerability aligns closely with CWE-400, which covers Uncontrolled Resource Consumption, and potentially CWE-269, Improper Privilege Management, depending on whether the disablement is an unintended side effect of legitimate administrative actions or a result of insufficient checks preventing misuse of those privileges. The attack vector involves leveraging existing high-level permissions to execute specific commands that lead to service degradation or complete unavailability. This could manifest as the database engine becoming unresponsive, refusing new connections, or failing to process queries due to corrupted internal states or exhausted resources triggered by the privileged action. Such a flaw undermines the principle of least privilege and highlights gaps in defensive programming practices where administrative functions are not sufficiently sandboxed from causing systemic failure.
The operational impact of this vulnerability is severe for organizations relying on IBM Db2 for critical data operations, as it directly compromises the availability pillar of the CIA triad. A successful exploitation results in a denial of service that can halt business processes dependent on real-time database access. Since the attack requires privileged access, the threat model focuses heavily on insider threats or compromised administrative credentials. An attacker who gains control of an admin account could use this flaw to cause significant downtime without needing to escalate privileges further or exploit external network-facing services. This makes detection and prevention challenging because the actions appear as legitimate administrative activity until the service disruption occurs, potentially leading to extended recovery times and data integrity concerns if transactions are interrupted mid-processing.
Mitigation strategies must focus on both technical controls and procedural safeguards given the privileged nature of the required access vector. Organizations should immediately apply the latest security patches provided by IBM for the affected Db2 versions to address the underlying code flaw that allows this service disablement. In addition to patching, implementing strict role-based access control is essential to limit the number of users with high-level privileges and ensure that such accounts are closely monitored. Multi-factor authentication should be enforced for all administrative logins to reduce the risk of credential compromise leading to exploitation. Furthermore, deploying database activity monitoring tools can help detect anomalous patterns associated with this specific denial-of-service trigger, allowing security teams to respond rapidly before significant operational disruption occurs. Regular audits of privileged user activities and reviewing system logs for unusual service state changes are critical components of a defense-in-depth strategy against this type of insider or compromised-account threat.