CVE-2026-71064 in Database Server
Summary
by MITRE • 08/19/2026
Vulnerability in the Portable Clusterware component of Oracle Database Server. Supported versions that are affected are 19.3-19.32, 21.3-21.23 and 23.4.0-23.26.3. Easily exploitable vulnerability allows unauthenticated attacker with access to the physical communication segment attached to the hardware where the Portable Clusterware executes to compromise Portable Clusterware. While the vulnerability is in Portable Clusterware, attacks may significantly impact additional products (scope change). Successful attacks of this vulnerability can result in takeover of Portable Clusterware. CVSS 3.1 Base Score 9.6 (Confidentiality, Integrity and Availability impacts). CVSS Vector: (CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H).
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Analysis
by VulDB Data Team • 08/19/2026
The identified vulnerability resides within the Portable Clusterware component of Oracle Database Server, affecting supported versions including 19.3 through 19.32, 21.3 through 21.23, and 23.4.0 through 23.26.3. This critical security flaw allows an unauthenticated attacker to compromise the integrity of the cluster management infrastructure by exploiting weaknesses in how the component handles communication over physical network segments. The vulnerability is characterized by its ease of exploitation, requiring no prior authentication or user interaction, which significantly lowers the barrier for malicious actors seeking to disrupt database operations or gain unauthorized control.
From a technical perspective, the flaw enables an attacker with access to the physical communication segment attached to the hardware where Portable Clusterware executes to take over the cluster management processes. This level of access typically implies that the attacker is on the same local network segment as the affected servers, such as within a data center LAN or a private cloud infrastructure. The absence of authentication requirements means that any entity capable of sending packets to this specific service can attempt exploitation without needing valid credentials. This aligns with Common Weakness Enumeration (CWE) categories related to insufficient authentication and improper access control mechanisms in network services.
The operational impact of this vulnerability is severe, as indicated by a CVSS 3.1 Base Score of 9.6 out of 10. The vector string AV:A/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H reflects high availability, low attack complexity, no privileges required, and no user interaction needed for exploitation. Crucially, the scope change indicator (S:C) signifies that while the vulnerability is located in Portable Clusterware, successful exploitation can lead to a compromise of additional products beyond just the cluster management software itself. This cascading effect means that an attacker who gains control over Portable Clusterware may be able to manipulate database instances, alter configurations, or disrupt services across multiple nodes within the cluster environment.
The consequences of such a takeover are multifaceted and devastating for enterprise environments. High impacts on confidentiality mean sensitive data stored in the databases managed by this cluster could be exfiltrated without detection. Integrity impacts suggest that an attacker could modify database contents, corrupt backups, or alter configuration settings to establish persistence or cause logical errors. Availability impacts indicate that the attacker can disrupt service availability, leading to downtime for critical business applications relying on these Oracle Database instances. This scenario is consistent with ATT&CK techniques involving initial access via network services and subsequent privilege escalation within the cluster management plane.
Mitigation strategies must prioritize immediate patching of all affected versions as soon as security updates from Oracle are applied. Organizations should verify their inventory against the specified version ranges to ensure comprehensive coverage. In addition to software remediation, network segmentation is a vital defensive measure. By isolating database servers and cluster communication channels into dedicated VLANs or subnets with strict access control lists, organizations can limit exposure to untrusted physical segments. Implementing mutual authentication protocols for inter-node communications where possible further reduces the risk of unauthorized entities injecting malicious commands into the cluster management traffic. Regular monitoring of network logs for anomalous activity directed at clusterware ports is also recommended to detect potential exploitation attempts in real time.