---
id: "CVE-2026-91659"
kind: "vulnerability"
aliases: ["CVE-2026-91659"]
title: "Oracle Essbase Build component flaw exposes critical data over HTTP"
severity: "high"
cvss: 7.7
epss: 0.00228
exploited: false
status: "open"
category: "vendor"
products: [{"name": "oracle essbase", "fixed": [], "affected": "= 21.8.3.0.0", "ecosystem": "vendor"}]
ecosystems: ["vendor"]
tags: ["oracle-essbase", "self-hosted", "vendor"]
not_affected_if: ["auth-required"]
published_at: "2026-10-20T22:21:06+00:00"
first_seen_at: "2026-10-23T21:57:27+00:00"
updated_at: "2026-10-25T03:10:33+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-91659", "first_seen_at": "2026-10-23T21:57:27+00:00"}, {"source": "epss", "url": "https://api.first.org/data/v1/epss?cve=CVE-2026-91659", "first_seen_at": "2026-10-24T13:15:55+00:00"}]
---

# Oracle Essbase Build component flaw exposes critical data over HTTP

A flaw in the Build component of Oracle Essbase 21.8.3.0.0 lets a low-privileged user reach data over HTTP. The sources say a successful attack gives unauthorized access to critical data and all Essbase-accessible data, with scope change to other products.

_Summary, check and fix written by a model from the sources; labelled as such._

## Affected

- vendor:oracle essbase affected = 21.8.3.0.0 fixed ?

## How to check

- Confirm the installed Essbase version against `21.8.3.0.0`
- unknown

## Fix

- Apply the Oracle Critical Patch Update fix for Essbase; the fixed version is unknown from the sources

## Timeline

- 2026-10-23T21:57:27+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-91659
- 2026-10-24T13:15:55+00:00 epss https://api.first.org/data/v1/epss?cve=CVE-2026-91659

## From the sources

Vulnerability in Oracle Essbase (component: Build).   The supported version that is affected is 21.8.3.0.0. Easily exploitable vulnerability allows low privileged attacker with network access via HTTP 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 7.7 (Confidentiality impacts).  CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N).

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