---
title: "CVE-2026-91644: Oracle Essbase - Authentication Bypass"
description: "Oracle Essbase 21.8.3.0.0 contains an authentication bypass caused by a security flaw, letting unauthenticated attackers with network access via HTTP gain unauthorized access and modify critical data, exploit requires network access."
url: https://panop.io/threat-heartbeat/CVE-2026-91644/
---

# CVE-2026-91644 Oracle Essbase - Authentication Bypass

Oracle Essbase 21.8.3.0.0 contains an authentication bypass caused by a security flaw, letting unauthenticated attackers with network access via HTTP gain unauthorized access and modify critical data, exploit requires network access.

CVSS base score 9.3 /10

Critical

CISA KEV

Not listed

Public exploit

None known

Authentication

Not required

[View the NVD record ↗](https://nvd.nist.gov/vuln/detail/CVE-2026-91644)

## Details

Type

Authentication Bypass

Impact

Information Disclosure, Data Tampering

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:L/A:N

Published

20 October 2026

Updated

21 October 2026

## Vendor fix

Update to the latest available version beyond 21.8.3.0.0.

Patching closes this CVE. It does not tell you which of your systems run the affected version, or what else is exposed alongside them.

## References

- [https://nvd.nist.gov/vuln/detail/CVE-2026-91644](https://nvd.nist.gov/vuln/detail/CVE-2026-91644)
- [https://www.oracle.com/security-alerts/cpuoct2026.html](https://www.oracle.com/security-alerts/cpuoct2026.html)

[← All CVEs](https://panop.io/threat-heartbeat/)

## What this record can't tell you

- Whether you run the affected software, and where
- Whether an attacker can actually reach and exploit it
- The misconfigurations that never get a CVE number
- What it would cost the business, ranked into what to fix first

Panop answers these inside your environment, for this CVE and every other finding.

[Book a demo](https://panop.io/demo)