---
id: "CVE-2026-91563"
kind: "vulnerability"
aliases: ["CVE-2026-91563"]
title: "Oracle Database OLAP: low-privilege user with DBMS_AW can take over"
severity: "high"
cvss: 8.8
epss: 0.00362
exploited: false
status: "open"
category: "package"
products: [{"name": "Oracle Database Server", "fixed": [], "affected": "19.3-19.32, 21.3-21.23, 23.4.0-23.26.3", "ecosystem": "vendor"}]
ecosystems: ["vendor"]
tags: ["oracle-database", "oracle-olap", "package", "self-hosted"]
not_affected_if: ["auth-required", "managed-hosting", "olap-not-installed", "unknown"]
published_at: "2026-10-20T22:20:59+00:00"
first_seen_at: "2026-10-23T21:57:27+00:00"
updated_at: "2026-10-25T12:38:51+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-91563", "first_seen_at": "2026-10-23T21:57:27+00:00"}, {"source": "analyst", "url": null, "first_seen_at": "2026-10-23T23:52:02+00:00"}, {"source": "epss", "url": "https://api.first.org/data/v1/epss?cve=CVE-2026-91563", "first_seen_at": "2026-10-25T12:38:51+00:00"}]
---

# Oracle Database OLAP: low-privilege user with DBMS_AW can take over

Oracle Database Server OLAP component flaw (Oct 2026 CPU). A low-privileged user holding the DBMS_AW privilege can take over Oracle OLAP over Oracle Net. CVSS 8.8, with high confidentiality, integrity and availability impact. Affects 19.3-19.32, 21.3-21.23 and 23.4.0-23.26.3.

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

## Affected

- vendor:Oracle Database Server affected 19.3-19.32, 21.3-21.23, 23.4.0-23.26.3 fixed ?

## How to check

Check the version: SELECT banner_full FROM v$version, or opatch lspatches, and compare with the affected ranges. Check whether OLAP is installed: SELECT comp_id, status FROM dba_registry WHERE comp_id='OLAP'. Check who holds the privilege: SELECT grantee FROM dba_tab_privs WHERE table_name='DBMS_AW' (also check dba_role_privs for roles granting it). If OLAP is not installed and nobody has DBMS_AW, exposure is likely low, though Oracle's patch doc is the authority.

## Fix

Apply the Oracle October 2026 Critical Patch Update for your release (via My Oracle Support patch availability document for Database); this means moving past 19.32, 21.23 and 23.26.3. Exact RU numbers not read. Workaround from Oracle and Armis: revoke DBMS_AW (and EXECUTE on it) from accounts that do not need it; this disables OLAP analytic workspace use for them.

## Timeline

- 2026-10-23T21:57:27+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-91563
- 2026-10-23T23:52:02+00:00 analyst — Confirmed in Oracle CPU Oct 2026 (listed under Oracle Database Server 19.3-19.32, 21.3-21.23, 23.4.0-23.26.3) and CVE record: CVSS 8.8, AV:N/PR:L. Exact RU/patch numbers sit in the MOS patch availability doc (login needed), not read. Armis says patched beyond 19.32/21.23/23.26.3, which is a secondary source. OLAP default-enabled status not found. No exploitation or PoC found; X not searched.
- 2026-10-25T12:38:51+00:00 epss https://api.first.org/data/v1/epss?cve=CVE-2026-91563

## Documents

- [advisory] Oracle Critical Patch Update Advisory - October 2026 https://www.oracle.com/security-alerts/cpuoct2026.html
- [advisory] CVE Record: CVE-2026-91563 https://www.cve.org/CVERecord?id=CVE-2026-91563
- [mitigation] CVE-2026-91563 Armis (mitigation: revoke DBMS_AW) https://cve.armis.com/CVE-2026-91563

## From the sources

Vulnerability in the Oracle OLAP component of Oracle Database Server.  Supported versions that are affected are 19.3-19.32, 21.3-21.23 and  23.4.0-23.26.3. Easily exploitable vulnerability allows low privileged attacker having DBMS_AW privilege with network access via Oracle Net to compromise Oracle OLAP.  Successful attacks of this vulnerability can result in takeover of Oracle OLAP. CVSS 3.1 Base Score 8.8 (Confidentiality, Integrity and Availability impacts).  CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H).

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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_