CVE-2026-91647 in Essbase
Summary
by MITRE • 10/21/2026
Vulnerability in Oracle Essbase (component: Security). The supported version that is affected is 21.8.3.0.0. Difficult to exploit vulnerability allows unauthenticated attacker with network access via TCP to compromise Oracle Essbase. Successful attacks of this vulnerability can result in takeover of Oracle Essbase. CVSS 3.1 Base Score 8.1 (Confidentiality, Integrity and Availability impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H).
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Analysis
by VulDB Data Team • 10/21/2026
The identified vulnerability resides within the security component of Oracle Essbase version 21.8.3.0.0, representing a critical risk to organizations relying on this enterprise analytics platform for business intelligence and data analysis operations. Although the exploitability is classified as difficult due to high complexity requirements, the severity rating remains significant with a CVSS v3.1 base score of 8.1 indicating High severity. This scoring reflects that while an attacker must navigate complex conditions to trigger the flaw, the potential consequences upon successful exploitation are severe and comprehensive affecting confidentiality integrity and availability simultaneously. The vulnerability allows for unauthenticated access meaning no valid credentials or prior authentication is required to initiate the attack vector which operates over standard TCP network connections thereby exposing the service to any entity capable of reaching the target host across internal networks or potentially the internet if misconfigured.
From a technical perspective this flaw likely involves improper validation or handling of security controls within the Essbase application layer allowing an attacker to bypass intended restrictions and execute arbitrary actions with elevated privileges. The absence of authentication requirements suggests that the vulnerability may stem from insecure default configurations missing access control checks on specific API endpoints or logic errors in how session tokens are validated during initial connection phases. Such weaknesses often align with CWE-287 Improper Authentication where the system fails to correctly verify identity before granting access and potentially CWE-940 Improper Verification of Authorization Complexity which permits privilege escalation through complex but achievable attack sequences. The high complexity requirement implies that successful exploitation may depend on specific environmental conditions timing or precise sequence of requests making it less susceptible to automated widespread attacks compared to simpler flaws yet still posing a substantial threat from determined adversaries with sufficient technical expertise and network proximity.
The operational impact of this vulnerability is profound as confirmed by the CVSS vector components which all indicate high impacts across confidentiality integrity and availability categories. A successful compromise enables an attacker to take complete control over the Oracle Essbase instance effectively achieving system takeover. This level of access allows for unauthorized reading sensitive business data stored within multidimensional cubes leading to significant data breaches violating regulatory compliance frameworks such as GDPR HIPAA or SOX depending on industry context it also permits modification or deletion of critical analytical models and configurations disrupting decision-making processes based on corrupted data furthermore the ability to alter system state can lead to denial of service conditions by consuming resources crashing services or locking out legitimate administrators. In enterprise environments where Essbase serves as a backbone for financial reporting supply chain analytics or sales forecasting such disruptions carry direct financial implications and reputational damage alongside potential legal liabilities arising from exposed customer information or insider data.
Mitigation strategies must prioritize immediate patching to the latest supported version of Oracle Essbase which addresses these security deficiencies through updated authentication mechanisms improved input validation and hardened default configurations if upgrading is not immediately feasible organizations should implement robust network segmentation isolating Essbase servers within restricted zones accessible only by authorized application tiers rather than exposing them directly via TCP ports. Additionally deploying web application firewalls with rules tailored to detect anomalous request patterns associated with exploitation attempts can provide a layer of defense in depth while strict access control lists restrict source IP addresses allowed to communicate with the service enabling multi-factor authentication for any administrative interfaces and conducting regular vulnerability assessments using automated scanning tools configured to identify unauthenticated entry points are essential steps toward reducing exposure. Continuous monitoring through security information and event management systems should be enhanced to alert on suspicious login attempts or unusual resource consumption patterns indicative of exploitation activity ensuring rapid incident response capabilities are in place to contain potential breaches before they escalate into full system compromise.