# CVE-2026-105820: Vault ACL Policy Cache Vulnerable to Cross-Namespace Policy Resolution

> Attackers can use path traversal in policy names to access capabilities from other namespaces, including root, in Vault Enterprise.

- **Severity:** Medium 5.4 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N`)
- **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:** 7 Oct 2026
- **Updated:** 8 Oct 2026
- **Also known as:** BIT-vault-2026-105820, GHSA-4rj6-p7m7-65jf, MINI-ffm2-qcfx-3vqc

## What is CVE-2026-105820?

CVE-2026-105820 is a medium-severity path traversal vulnerability in HashiCorp Vault Enterprise, published on 7 Oct 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

Vault's ACL policy cache allowed namespace traversal when policy names contained path traversal constructs. This may allow a token assigned specially crafted policy names to use the capabilities of policies defined in other namespaces, including the root namespace. This vulnerability (CVE-2026-105820) is fixed in Vault Enterprise 2.1.2, 1.21.12, 1.20.17, and 1.19.23. Vault Community Edition does not support namespaces, and is not affected.

Weakness: CWE-22 (Improper Limitation of a Pathname to a Restricted Directory)

## Which versions are affected by CVE-2026-105820?

1 open source package ship an affected version, including vault.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `vault` | Bitnami | From 0.0.1 | 1.19.23, 1.20.17, 1.21.12, 2.1.2 |

## How do I fix CVE-2026-105820?

Upgrade vault to a fixed version for your release line: 1.19.23, 1.20.17, 1.21.12 or 2.1.2.

## Is CVE-2026-105820 being exploited?

There is no known exploitation of CVE-2026-105820 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-105820 and fix it if it is affected.

What it is: CVE-2026-105820 is a medium-severity path traversal vulnerability in HashiCorp Vault Enterprise, published on 7 Oct 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-2026-105820 in the wild and no public exploit code.

Affected packages and fixed versions:
- vault (Bitnami): affected from 0.0.1; fixed in 1.19.23, 1.20.17, 1.21.12, 2.1.2

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-2026-105820/ (Markdown: https://insights.sbomify.com/CVE-2026-105820/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-105820
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-105820
- OSV: https://osv.dev/vulnerability/CVE-2026-105820

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-105820/
Summaries are generated and may contain mistakes; the official description above is the record.