---
id: CVE-2026-91663
title: 'Vulnerability in Oracle Essbase (component: Security)'
summary: >-
  Vulnerability in Oracle Essbase (component: Security).   The supported version
  that is affected is 21.8.3.0.0. Easily exploitable vulnerability allows low
  privileged attacker with network access via T3, IIOP to compromise Oracle
  Essbase.…
severity: critical
cvss: 9.9
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H'
cvssSource: cna
vendor: Oracle Corporation
product: Oracle Essbase
affected:
  - oracle_essbase 21.8.3.0.0
published: '2026-10-20'
updated: '2026-10-20'
sourceUpdated: '2026-10-20T21:26:55.534Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-91663'
references:
  - url: 'https://www.oracle.com/security-alerts/cpuoct2026.html'
    label: Oracle Advisory
tags:
  - cve.org
ingestedAt: '2026-10-20T22:23:33.700Z'
---

## Overview

Vulnerability in Oracle Essbase (component: Security).   The supported version that is affected is 21.8.3.0.0. Easily exploitable vulnerability allows low privileged attacker with network access via T3, IIOP 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 takeover of Oracle Essbase. CVSS 3.1 Base Score 9.9 (Confidentiality, Integrity and Availability impacts).  CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H).

## Affected

- `oracle_essbase 21.8.3.0.0`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.