---
id: CVE-2021-38155
aliases:
  - GHSA-4225-97pr-rr52
  - PYSEC-2026-830
title: OpenStack Keystone allows information disclosure during account locking
summary: OpenStack Keystone allows information disclosure during account locking
severity: high
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N'
vendor: keystone
product: keystone
ecosystem: pip
affected:
  - 'keystone >= 10.0, < 16.0.2'
  - 'keystone >= 17.0, < 17.0.1'
  - 'keystone >= 18.0, < 18.0.1'
  - 'keystone >= 19.0, < 19.0.1'
patched:
  - keystone 16.0.2
  - keystone 17.0.1
  - keystone 18.0.1
  - keystone 19.0.1
published: '2022-05-24'
updated: '2026-07-07'
source: OSV
sourceUrl: 'https://osv.dev/vulnerability/GHSA-4225-97pr-rr52'
references:
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2021-38155'
  - url: >-
      https://github.com/openstack/keystone/commit/1b573ae7d1c20e0ebfbde79bbe7538a09589c75d
  - url: >-
      https://github.com/openstack/keystone/commit/8ab4eb27be4c13c9bab2b3ea700f00a190521bf8
  - url: >-
      https://github.com/openstack/keystone/commit/ac2631ae33445877094cdae796fbcdce8833a626
  - url: 'https://github.com/openstack/keystone'
  - url: 'https://launchpad.net/bugs/1688137'
  - url: 'https://lists.debian.org/debian-lts-announce/2024/01/msg00007.html'
  - url: 'https://security.openstack.org/ossa/OSSA-2021-003.html'
  - url: 'http://www.openwall.com/lists/oss-security/2021/08/10/5'
tags:
  - osv
  - pip
epss: 0.02478
epssPercentile: 0.83894
ingestedAt: '2026-07-08T18:25:45.217Z'
---

## Overview

OpenStack Keystone 10.x through 16.x before 16.0.2, 17.x before 17.0.1, 18.x before 18.0.1, and 19.x before 19.0.1 allows information disclosure during account locking (related to PCI DSS features). By guessing the name of an account and failing to authenticate multiple times, any unauthenticated actor could both confirm the account exists and obtain that account's corresponding UUID, which might be leveraged for other unrelated attacks. All deployments enabling security_compliance.lockout_failure_attempts are affected.

## Affected packages

- `keystone >= 10.0, < 16.0.2`
- `keystone >= 17.0, < 17.0.1`
- `keystone >= 18.0, < 18.0.1`
- `keystone >= 19.0, < 19.0.1`

## Remediation

Upgrade to a patched release:

- `keystone 16.0.2`
- `keystone 17.0.1`
- `keystone 18.0.1`
- `keystone 19.0.1`