# CVE-2026-43000: OpenStack Keystone has an Incorrect Authorization issue

> Attackers with member role can escalate to admin by chaining application credentials and trusts, impersonating victims to bypass role validation.

- **Severity:** Medium 6.0 (`CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:L/I:L/A:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 28 May 2026
- **Updated:** 24 Jul 2026
- **Also known as:** DEBIAN-CVE-2026-43000, GHSA-q623-f4j4-p4xj, PYSEC-2026-601

## What is CVE-2026-43000?

CVE-2026-43000 is a medium-severity vulnerability in OpenStack Keystone, published on 28 May 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

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.

Weakness: CWE-266 (Incorrect Privilege Assignment), CWE-863 (Incorrect Authorization)

## Which versions are affected by CVE-2026-43000?

7 open source packages ship an affected version, including keystone. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `keystone` | PyPI | From 14.0.0 | 27.0.2, 28.0.2, 29.0.2 |
| `keystone` | PyPI | From 14.0.0 | 27.0.2 |
| `keystone` | PyPI | From 14.0.0 | 27.0.2 |
| `keystone` | PyPI | From 28.0.0 | 28.0.2 |
| `keystone` | PyPI | From 28.0.0 | 28.0.2 |
| `keystone` | PyPI | From 29.0.0 | 29.0.2 |
| `keystone` | PyPI | From 29.0.0 | 29.0.2 |

Products: Openstack Keystone.

## How do I fix CVE-2026-43000?

Upgrade keystone to a fixed version for your release line: 27.0.2, 28.0.2 or 29.0.2.

## Is CVE-2026-43000 being exploited?

There is no known exploitation of CVE-2026-43000 in the wild and no public exploit code.

## Other vulnerabilities in OpenStack Keystone

- [CVE-2020-12690](https://insights.sbomify.com/CVE-2020-12690/): Insufficient Session Expiration in OpenStack Keystone (high 8.8)
- [CVE-2019-19687](https://insights.sbomify.com/CVE-2019-19687/): OpenStack Keystone Credential Leakage (high 8.8)
- [CVE-2026-43001](https://insights.sbomify.com/CVE-2026-43001/): OpenStack Keystone has an Incorrect Authorization Issue (high 7.9)
- [CVE-2014-2828](https://insights.sbomify.com/CVE-2014-2828/): OpenStack Identity (Keystone) DoS through V3 API authentication chaining (high 7.8)
- [CVE-2021-38155](https://insights.sbomify.com/CVE-2021-38155/): OpenStack Keystone allows information disclosure during account locking (high 7.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-43000 and fix it if it is affected.

What it is: CVE-2026-43000 is a medium-severity vulnerability in OpenStack Keystone, published on 28 May 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-43000 in the wild and no public exploit code.

Affected packages and fixed versions:
- keystone (PyPI): affected from 14.0.0; fixed in 27.0.2, 28.0.2, 29.0.2
- keystone (PyPI): affected from 14.0.0; fixed in 27.0.2
- keystone (PyPI): affected from 14.0.0; fixed in 27.0.2
- keystone (PyPI): affected from 28.0.0; fixed in 28.0.2
- keystone (PyPI): affected from 28.0.0; fixed in 28.0.2
- keystone (PyPI): affected from 29.0.0; fixed in 29.0.2
- keystone (PyPI): affected from 29.0.0; fixed in 29.0.2

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-43000/ (Markdown: https://insights.sbomify.com/CVE-2026-43000/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-43000
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-43000
- OSV: https://osv.dev/vulnerability/CVE-2026-43000

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-43000/
Summaries are generated and may contain mistakes; the official description above is the record.