---
id: "CVE-2026-91391"
kind: "vulnerability"
aliases: ["CVE-2026-91391"]
title: "Oracle Siebel CRM End User: Open UI flaw leaks some stored data"
severity: "low"
cvss: 3.7
epss: 0.00258
exploited: false
status: "open"
category: "vendor"
products: []
ecosystems: []
tags: ["oracle", "self-hosted", "siebel-crm", "vendor"]
not_affected_if: ["not-siebel-crm"]
published_at: "2026-10-20T22:20:42+00:00"
first_seen_at: "2026-10-23T21:57:26+00:00"
updated_at: "2026-10-25T12:38:52+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-91391", "first_seen_at": "2026-10-23T21:57:26+00:00"}, {"source": "epss", "url": "https://api.first.org/data/v1/epss?cve=CVE-2026-91391", "first_seen_at": "2026-10-25T12:38:52+00:00"}]
---

# Oracle Siebel CRM End User: Open UI flaw leaks some stored data

Oracle Siebel CRM End User, in the Open UI component, has a flaw that lets an unauthenticated attacker on the network send HTTP requests and read a subset of data the application can access. The attack is hard to carry out, and the CVSS 3.1 score is 3.7 with only confidentiality affected.

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

## How to check

- Identify whether the environment runs Siebel CRM End User with supported versions `17.0` through `26.9`
- unknown for further checks, the sources do not say

## Fix

- Apply the Oracle Siebel CRM patch or update for the affected Open UI component; the sources do not name the fixed version
- unknown for other actions, the sources do not say

## Timeline

- 2026-10-23T21:57:26+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-91391
- 2026-10-25T12:38:52+00:00 epss https://api.first.org/data/v1/epss?cve=CVE-2026-91391

## From the sources

Vulnerability in the Siebel CRM End User product of Oracle Siebel CRM (component: Open UI).  Supported versions that are affected are 17.0-26.9. Difficult to exploit vulnerability allows unauthenticated attacker with network access via HTTP to compromise Siebel CRM End User.  Successful attacks of this vulnerability can result in  unauthorized read access to a subset of Siebel CRM End User accessible data. CVSS 3.1 Base Score 3.7 (Confidentiality impacts).  CVSS Vector: (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/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_