---
id: "CVE-2026-91458"
kind: "vulnerability"
aliases: ["CVE-2026-91458"]
title: "Oracle Outside In: local flaw lets a user take over the component"
severity: "high"
cvss: 7.8
epss: 0.00124
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["fusion-middleware", "oracle", "outside-in", "package", "self-hosted"]
not_affected_if: ["not-installed"]
published_at: "2026-10-20T22:20:49+00:00"
first_seen_at: "2026-10-23T21:57:27+00:00"
updated_at: "2026-10-25T12:38:52+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-91458", "first_seen_at": "2026-10-23T21:57:27+00:00"}, {"source": "epss", "url": "https://api.first.org/data/v1/epss?cve=CVE-2026-91458", "first_seen_at": "2026-10-25T12:38:52+00:00"}]
---

# Oracle Outside In: local flaw lets a user take over the component

Oracle Outside In Technology, a file-parsing library bundled in Oracle Fusion Middleware, has a flaw in its Outside In Core component that affects version 8.5.8. An attacker with logon access to the host where it runs can take over the product when another person opens or processes a crafted file.

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

## How to check

- Check whether Oracle Outside In Technology is installed on the host, for example under the Oracle Fusion Middleware home directory.
- Confirm the installed version against `8.5.8` in the Oracle Fusion Middleware installation.

## Fix

- Apply the Oracle Critical Patch Update that addresses CVE-2026-91458 for Oracle Outside In Technology.
- Fixed version: unknown

## Timeline

- 2026-10-23T21:57:27+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-91458
- 2026-10-25T12:38:52+00:00 epss https://api.first.org/data/v1/epss?cve=CVE-2026-91458

## From the sources

Vulnerability in the Oracle Outside In Technology product of Oracle Fusion Middleware (component: Outside In Core).   The supported version that is affected is 8.5.8. Easily exploitable vulnerability allows unauthenticated attacker with logon to the infrastructure where Oracle Outside In Technology executes to compromise Oracle Outside In Technology.  Successful attacks require human interaction from a person other than the attacker. Successful attacks of this vulnerability can result in takeover of Oracle Outside In Technology. CVSS 3.1 Base Score 7.8 (Confidentiality, Integrity and Availability impacts).  CVSS Vector: (CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H).

---

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