---
id: "CVE-2026-91393"
kind: "vulnerability"
aliases: ["CVE-2026-91393"]
title: "Oracle Siebel CRM End User: Open UI flaw allows limited data changes"
severity: "low"
cvss: 3.1
epss: 0.00119
exploited: false
status: "open"
category: "vendor"
products: []
ecosystems: []
tags: ["enterprise-crm", "oracle", "siebel-crm", "vendor"]
not_affected_if: ["no-network-exposure", "unsupported-version-outside-range"]
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-2026-91393", "first_seen_at": "2026-10-23T21:57:26+00:00"}, {"source": "epss", "url": "https://api.first.org/data/v1/epss?cve=CVE-2026-91393", "first_seen_at": "2026-10-25T12:38:52+00:00"}]
---

# Oracle Siebel CRM End User: Open UI flaw allows limited data changes

Oracle Siebel CRM End User, versions 17.0 through 26.9, has a flaw in its Open UI component. An unauthenticated attacker on the network can, with a victim's help, make unauthorized updates, inserts or deletes to some data the end user can access.

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

## How to check

- Confirm whether Siebel CRM End User is deployed and which release runs, using the version shown in the Siebel installation or Oracle's release notes.
- Check whether the Open UI component is in use.

## Fix

- Move to a Siebel CRM release fixed by Oracle's Critical Patch Update (the fixed version is unknown from the sources).
- Apply the Oracle Critical Patch Update for the affected release.

## Timeline

- 2026-10-23T21:57:26+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-91393
- 2026-10-25T12:38:52+00:00 epss https://api.first.org/data/v1/epss?cve=CVE-2026-91393

## 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 require human interaction from a person other than the attacker. Successful attacks of this vulnerability can result in  unauthorized update, insert or delete access to some of Siebel CRM End User accessible data. CVSS 3.1 Base Score 3.1 (Integrity impacts).  CVSS Vector: (CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:L/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_