KeystoneApplication · Openstack

CVE-2026-42998

HIGH · 8.8 CVSS v3.1 Published 2026-05-28
Fix available
A fix is available. Upgrade to 27.0.2 / 28.0.2 or later.
See remediation →
94/100
Remediation priority · Urgent
Public exploit Remotely reachable Zero-click Patch available

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
An issue was discovered in OpenStack Keystone before 29.0.2. The Keystone application credential authentication plugin does not verify that the user supplied in the authentication request matches the owner of the application credential. An attacker can authenticate with their own application credential ID and secret while specifying a different user's name and domain in the request body. Keystone issues a token attributed to the victim user. The impersonated token is project-scoped and carries the intersection of the application credential's roles and the victim's actual roles on the project. This enables audit evasion, reading the victim's credentials, and acting as the victim within shared projects.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis
How this class of weakness works · CWE-863

An authorization check exists but is flawed, so it passes when it should fail. Attackers probe roles and object references to find the gap. Remediation means centralising and correctly implementing the access-control logic, then testing it against every role.

General guidance for the incorrect authorization class — the official description and references above are authoritative for this specific CVE. Want a bespoke review and a reviewed fix? Ask our team →

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
KeystoneApplication
Affected:>= 14.0.0, < 27.0.2>= 28.0.0, < 28.0.2>= 29.0.0, < 29.0.2

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 27.0.2 / 28.0.2 / 29.0.2 or later
Fixed in 27.0.228.0.229.0.2
Vendor patch bugs.launchpad.net →
Recommended fix High confidence

29.0.2 (or 28.0.2/27.0.2 depending on your branch)

  1. Identify current Keystone version using 'keystone --version' or checking the package manager
  2. Review the OpenStack Keystone upgrade documentation for your deployment (https://docs.openstack.org/keystone/latest/)
  3. Plan the upgrade considering your current branch (14.x-26.x upgrade to 27.0.2, 28.x upgrade to 28.0.2, or 29.x upgrade to 29.0.2)
  4. Create a backup of the Keystone database and configuration files (/etc/keystone/)
  5. Stop the Keystone services
  6. Upgrade the Keystone package using your package manager (e.g., 'apt-get update && apt-get install keystone' or 'yum update openstack-keystone')
  7. Run database migrations if required ('keystone-manage db_sync')
  8. Start the Keystone services
Caveat OpenStack upgrades may have API or configuration changes; review release notes for your version jump and test in a staging environment before production deployment

Generated from the published advisory — verify against the referenced sources before acting.

We can perform the upgrade in your staging environment and verify nothing breaks — typical engagement from $1,950. Get the upgrade done

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-42998 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data