CVE-2026-91633 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. Easily exploitable vulnerability allows high privileged attacker with logon to the infrastructure where Oracle Essbase executes to compromise Oracle Essbase. While the vulnerability is in Oracle Essbase, attacks may significantly impact additional products (scope change). Successful attacks of this vulnerability can result in unauthorized access to critical data or complete access to all Oracle Essbase accessible data. CVSS 3.1 Base Score 6.0 (Confidentiality impacts). CVSS Vector: (CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:N/A:N).
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Analysis
by VulDB Data Team • 10/21/2026
The identified vulnerability resides within the security component of Oracle Essbase, specifically affecting version 21.8.3.0.0 and potentially other supported releases depending on specific configuration states. This flaw represents a critical weakness in how the application handles authentication and authorization checks for high-privileged users who have already gained logon access to the underlying infrastructure hosting the Essbase service. The core technical issue involves an insufficient validation mechanism that allows an attacker with legitimate but elevated credentials to bypass intended security controls, thereby escalating their privileges or accessing data they are not authorized to view. This type of flaw is typically categorized under CWE-269 Improper Privilege Management or CWE-732 Incorrect Permission Assignment for Critical Resource within the Common Weakness Enumeration framework, indicating a failure in enforcing least privilege principles during runtime operations.
The operational impact of this vulnerability is severe due to its potential for scope change. Although the initial point of exploitation is confined to Oracle Essbase, successful exploitation can lead to lateral movement or data exfiltration that significantly impacts additional products within the enterprise environment. An attacker with high privileges who exploits this flaw can achieve unauthorized access to critical business intelligence data stored in Essbase cubes. This results in a high impact on confidentiality as defined by the CVSS 3.1 scoring model, which assigns a base score of 6.0 primarily driven by the complete compromise of confidential information. The attack vector is classified as Local with Low complexity and requires High privileges initially, meaning it cannot be exploited remotely over a network without prior access to the system, but once local high-privileged access is obtained, no user interaction is required for successful exploitation.
From an offensive security perspective, this vulnerability aligns with ATT&CK technique T1078 Valid Accounts, where attackers use legitimate credentials to maintain persistence and move laterally within a network. The ability to compromise Oracle Essbase in this manner suggests that the application may be integrated deeply into broader data warehousing or business intelligence architectures, making the breach of its security controls particularly damaging. Attackers could potentially extract sensitive financial forecasts, sales projections, or operational metrics that are stored within the Essbase environment, leading to significant competitive disadvantage or regulatory compliance failures for the affected organization.
Mitigation strategies must focus on both immediate remediation and long-term architectural hardening. The primary recommendation is to apply the latest security patches provided by Oracle as soon as they become available for version 21.8.3.0.0. Organizations should also review their access control policies to ensure that high-privileged accounts are strictly limited in number and usage, adhering to the principle of least privilege. Implementing multi-factor authentication for administrative interfaces can add a layer of defense against credential theft or misuse. Furthermore, network segmentation strategies should be employed to isolate Essbase servers from less trusted zones, reducing the attack surface available to potential intruders who might gain initial foothold on adjacent systems. Continuous monitoring and logging enhancements are also advised to detect anomalous access patterns that may indicate exploitation attempts of this vulnerability.