# CVE-2026-40264: OpenBao's Token Store Allows Cross-Namespace Renewal, Revocation

> A privileged administrator in one tenant can revoke or renew tokens in another tenant by exploiting cross-namespace token accessor handling.

- **Severity:** Low 2.0 (`CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** Yes
- **Published:** 21 Apr 2026
- **Updated:** 21 Apr 2026
- **Also known as:** BIT-openbao-2026-40264, GHSA-p49j-v9wc-wg57, GO-2026-5526

## What is CVE-2026-40264?

CVE-2026-40264 is a low-severity missing authorization vulnerability in openbao, published on 21 Apr 2026. An attacker needs administrator access to exploit it, and only if a user opens a file or follows a link.

### Official description

OpenBao is an open source identity-based secrets management system. OpenBao's namespaces provide multi-tenant separation. Prior to version 2.5.3, a tenant who leaks token accessors can have their token revoked or renewed by a privileged administrator in another tenant. This is addressed in v2.5.3.

Weakness: CWE-1259 (Improper Restriction of Security Token Assignment)

## Which versions are affected by CVE-2026-40264?

4 open source packages ship an affected version, including github.com/openbao/openbao and openbao. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `github.com/openbao/openbao` | Go | All versions | 0.0.0-20260420162526-f58111d2ca54 |
| `github.com/openbao/openbao` | Go | All versions | 0.0.0-20260420162526-f58111d2ca54 |
| `github.com/openbao/openbao` | Go | All versions | 0.0.0-20260420162526-f58111d2ca54 |
| `openbao` | Bitnami | All versions | 2.5.3 |

Products: Openbao Openbao.

## How do I fix CVE-2026-40264?

Upgrade github.com/openbao/openbao to 0.0.0-20260420162526-f58111d2ca54 or later.

## Is CVE-2026-40264 being exploited?

There is no known exploitation of CVE-2026-40264 in the wild and no public exploit code.

## Other vulnerabilities in openbao

- [CVE-2026-33757](https://insights.sbomify.com/CVE-2026-33757/): OpenBao lacks user confirmation for OIDC direct callback mode (critical 9.6)
- [CVE-2026-33758](https://insights.sbomify.com/CVE-2026-33758/): OpenBao has Reflected XSS in its OIDC authentication error message (critical 9.4)
- [CVE-2025-54997](https://insights.sbomify.com/CVE-2025-54997/): OpenBao: Privileged Operator May Execute Code on the Underlying Host (critical 9.1)
- [CVE-2025-64761](https://insights.sbomify.com/CVE-2025-64761/): OpenBao Privileged Operator Identity Group Root Escalation (high 7.5)
- [CVE-2025-59043](https://insights.sbomify.com/CVE-2025-59043/): OpenBao vulnerable to denial of service via malicious JSON request processing (high 7.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-40264 and fix it if it is affected.

What it is: CVE-2026-40264 is a low-severity missing authorization vulnerability in openbao, published on 21 Apr 2026. An attacker needs administrator access to exploit it, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2026-40264 in the wild and no public exploit code.

Affected packages and fixed versions:
- github.com/openbao/openbao (Go): affected all versions; fixed in 0.0.0-20260420162526-f58111d2ca54
- github.com/openbao/openbao (Go): affected all versions; fixed in 0.0.0-20260420162526-f58111d2ca54
- github.com/openbao/openbao (Go): affected all versions; fixed in 0.0.0-20260420162526-f58111d2ca54
- openbao (Bitnami): affected all versions; fixed in 2.5.3

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-2026-40264/ (Markdown: https://insights.sbomify.com/CVE-2026-40264/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-40264
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-40264
- OSV: https://osv.dev/vulnerability/CVE-2026-40264

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-40264/
Summaries are generated and may contain mistakes; the official description above is the record.