---
id: "CVE-2026-91426"
kind: "vulnerability"
aliases: ["CVE-2026-91426"]
title: "Oracle Siebel CRM Deployment: low-privilege local user reads critical data"
severity: "medium"
cvss: 5.5
epss: 0.00139
exploited: false
status: "open"
category: "vendor"
products: []
ecosystems: []
tags: ["on-prem", "oracle", "server-infrastructure", "siebel-crm", "vendor"]
not_affected_if: ["no-local-logon", "unsupported-version"]
published_at: "2026-10-20T22:20:45+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-2026-91426", "first_seen_at": "2026-10-23T21:57:26+00:00"}, {"source": "epss", "url": "https://api.first.org/data/v1/epss?cve=CVE-2026-91426", "first_seen_at": "2026-10-25T12:38:52+00:00"}]
---

# Oracle Siebel CRM Deployment: low-privilege local user reads critical data

Oracle Siebel CRM Deployment, in its Server Infrastructure component, has a flaw that lets a low-privileged user who can log on to the host access data they should not see. The sources describe high confidentiality impact (CVSS 5.5, local vector) with no integrity or availability impact.

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

## How to check

- Check the installed Siebel CRM Deployment version against the affected range 17.0-26.9 in the Oracle Siebel CRM advisory
- unknown for other checks; the sources do not name config files or commands

## Fix

- Apply the Oracle Siebel CRM Critical Patch Update that covers your release; the sources do not name a fixed version
- unknown for other actions

## Timeline

- 2026-10-23T21:57:26+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-91426
- 2026-10-25T12:38:52+00:00 epss https://api.first.org/data/v1/epss?cve=CVE-2026-91426

## From the sources

Vulnerability in the Siebel CRM Deployment product of Oracle Siebel CRM (component: Server Infrastructure).  Supported versions that are affected are 17.0-26.9. Easily exploitable vulnerability allows low privileged attacker with logon to the infrastructure where Siebel CRM Deployment executes to compromise Siebel CRM Deployment.  Successful attacks of this vulnerability can result in  unauthorized access to critical data or complete access to all Siebel CRM Deployment accessible data. CVSS 3.1 Base Score 5.5 (Confidentiality impacts).  CVSS Vector: (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N).

---

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