---
id: "CVE-2026-91642"
kind: "vulnerability"
aliases: ["CVE-2026-91642"]
title: "Oracle Essbase: unauthenticated HTTP flaw allows data change and partial denial of service"
severity: "high"
cvss: 7.3
epss: 0.00241
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: ["http-not-exposed", "no-essbase-deployment"]
published_at: "2026-10-20T22:21:04+00:00"
first_seen_at: "2026-10-23T21:57:27+00:00"
updated_at: "2026-10-25T03:27:23+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-91642", "first_seen_at": "2026-10-23T21:57:27+00:00"}, {"source": "epss", "url": "https://api.first.org/data/v1/epss?cve=CVE-2026-91642", "first_seen_at": "2026-10-24T13:15:55+00:00"}]
---

# Oracle Essbase: unauthenticated HTTP flaw allows data change and partial denial of service

Oracle Essbase 21.8.3.0.0 has a security flaw reachable over HTTP without a login. An attacker can read, change or delete some Essbase data and partly disrupt the service.

_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 Essbase version in use is `21.8.3.0.0` by checking the installed release in the Oracle Essbase server console or install directory
- Check whether the Essbase HTTP endpoint is reachable from untrusted networks

## Fix

- Apply the Oracle Critical Patch Update fix for Essbase; the fixed version is unknown from the sources
- Restrict network access to the Essbase HTTP interface until patched

## Timeline

- 2026-10-23T21:57:27+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-91642
- 2026-10-24T13:15:55+00:00 epss https://api.first.org/data/v1/epss?cve=CVE-2026-91642

## 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 unauthenticated attacker with network access via HTTP to compromise Oracle Essbase.  Successful attacks of this vulnerability can result in  unauthorized update, insert or delete access to some of Oracle Essbase accessible data as well as  unauthorized read access to a subset of Oracle Essbase accessible data and unauthorized ability to cause a partial denial of service (partial DOS) of Oracle Essbase. CVSS 3.1 Base Score 7.3 (Confidentiality, Integrity and Availability impacts).  CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L).

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