CVE-2021-38155

mediumpriority · track · 31EPSS 0.025 · 84 %ileEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

2.48% (84th) EPSS

CVSS 5 · medium

Is it mine?

9 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · osv · nvd

EPSS · scored 2026-10-27

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.

cvss

Technical severity, 0–10. One row per scoring source.

7.5

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5–7.5

v2.05mediumAV:N/AC:L/Au:N/C:P/I:N/A:Nprimary · NVD / NIST USexploitability 10 · impact 2.9

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:Nprimary · NVD / NIST USexploitability 3.9 · impact 3.6

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:Nsecondary · OSV

v3.16.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-307USprimaryCWE-307US

affected products (9)

Products and version ranges known to be affected.

n/a n/a≤ n/aenisa_euvdEU
openstack keystone10.0.0 → 16.0.2nvdUScpe:2.3:a:openstack:keystone:*:*:*:*:*:*:*:*
openstack keystone17.0.0 → 17.0.1nvdUScpe:2.3:a:openstack:keystone:*:*:*:*:*:*:*:*
openstack keystone18.0.0 → 18.0.1nvdUScpe:2.3:a:openstack:keystone:*:*:*:*:*:*:*:*
openstack keystone19.0.0 → 19.0.1nvdUScpe:2.3:a:openstack:keystone:*:*:*:*:*:*:*:*
PyPI keystone10.0 → 16.0.2osvUSpkg:pypi/keystone
PyPI keystone17.0 → 17.0.1osvUSpkg:pypi/keystone
PyPI keystone18.0 → 18.0.1osvUSpkg:pypi/keystone
PyPI keystone19.0 → 19.0.1osvUSpkg:pypi/keystone

advisories (2)

Vendor and ecosystem advisories describing this.

GHSA-4225-97pr-rr52OpenStack Keystone allows information disclosure during account locking2022-05-24ghsa · osvUS
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.
PYSEC-2026-830OpenStack Keystone allows information disclosure during account locking2026-07-06vendor · osvUS
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.

also known as (6)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd osv nvd NVD CVE.org MITRE

published 2021-08-06modified 2026-06-17

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references (14)

External citations — patches, advisories, analysis.

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