---
id: "CVE-2026-91631"
kind: "vulnerability"
aliases: ["CVE-2026-91631"]
title: "Oracle Essbase: low-privilege network attacker reads a subset of data"
severity: "medium"
cvss: 5.0
epss: 0.00295
exploited: false
status: "open"
category: "vendor"
products: [{"name": "oracle essbase", "fixed": [], "affected": "= 21.8.3.0.0", "ecosystem": "vendor"}]
ecosystems: ["vendor"]
tags: ["enterprise", "oracle-essbase", "self-hosted", "vendor"]
not_affected_if: ["no-essbase-deployment"]
published_at: "2026-10-20T22:21:03+00:00"
first_seen_at: "2026-10-23T21:57:27+00:00"
updated_at: "2026-10-25T04:30:39+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-91631", "first_seen_at": "2026-10-23T21:57:27+00:00"}, {"source": "epss", "url": "https://api.first.org/data/v1/epss?cve=CVE-2026-91631", "first_seen_at": "2026-10-24T13:15:55+00:00"}]
---

# Oracle Essbase: low-privilege network attacker reads a subset of data

Oracle Essbase's Security component has a flaw that lets a low-privileged user reach data over HTTP that they should not see. The sources report unauthorized read access to a subset of Essbase data, with a scope change that may extend impact 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 deployed Essbase version with the Oracle admin console or install records; the sources list `21.8.3.0.0` as affected
- Check Oracle's Critical Patch Update advisory for the Essbase patch level unknown

## Fix

- Apply the Oracle security update for Essbase listed in the Oracle advisory; the fixed version is unknown from the sources
- Restrict HTTP access to Essbase to trusted networks until patched

## Timeline

- 2026-10-23T21:57:27+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-91631
- 2026-10-24T13:15:55+00:00 epss https://api.first.org/data/v1/epss?cve=CVE-2026-91631

## From the sources

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 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 read access to a subset of Oracle Essbase accessible data. CVSS 3.1 Base Score 5.0 (Confidentiality impacts).  CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N).

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_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_