---
id: CVE-2026-43000
aliases:
  - GHSA-q623-f4j4-p4xj
  - PYSEC-2026-601
title: OpenStack Keystone has an Incorrect Authorization issue
summary: OpenStack Keystone has an Incorrect Authorization issue
severity: medium
cvss: 6
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:L/I:L/A:L'
vendor: keystone
product: keystone
ecosystem: pip
affected:
  - 'keystone >= 14.0.0, < 27.0.2'
  - 'keystone >= 28.0.0, < 28.0.2'
  - 'keystone >= 29.0.0, < 29.0.2'
patched:
  - keystone 27.0.2
  - keystone 28.0.2
  - keystone 29.0.2
published: '2026-05-28'
updated: '2026-09-10'
sourceUpdated: '2026-09-10T03:51:06.876418993Z'
source: OSV
sourceUrl: 'https://osv.dev/vulnerability/GHSA-q623-f4j4-p4xj'
references:
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-43000'
  - url: 'https://access.redhat.com/security/cve/CVE-2026-43000'
  - url: 'https://bugs.launchpad.net/keystone/+bug/2148477'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2482826'
  - url: 'https://github.com/openstack/keystone'
  - url: >-
      https://github.com/pypa/advisory-database/tree/main/vulns/keystone/PYSEC-2026-601.yaml
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-43000.json
  - url: 'https://security.openstack.org/ossa/OSSA-2026-015.html'
tags:
  - osv
  - pip
epss: 0.00425
epssPercentile: 0.34294
ingestedAt: '2026-07-08T18:25:52.104Z'
---

## Overview

An issue was discovered in OpenStack Keystone before 29.0.2. When combined with an application credential impersonation vulnerability, an attacker with the member role on a project can escalate to admin by chaining unrestricted application credentials with Keystone trusts. The impersonated token carries the victim's identity, which passes the trustor validation check. Keystone then validates the delegated roles against the victim's actual role assignments in the database, not the roles on the requesting token. This allows the attacker to create a trust delegating the victim's admin role to themselves. The trust persists independently, and additional trusts and application credentials can be created to maintain access. All actions are logged under the victim's identity.

## Affected packages

- `keystone >= 14.0.0, < 27.0.2`
- `keystone >= 28.0.0, < 28.0.2`
- `keystone >= 29.0.0, < 29.0.2`

## Remediation

Upgrade to a patched release:

- `keystone 27.0.2`
- `keystone 28.0.2`
- `keystone 29.0.2`