# CVE-2026-63131: OpenBao LIST ACL bypass: a trailing-slash LIST request skips a more-specific deny rule (unported Vault v2.0.3 fix)

> Attackers can bypass ACL deny rules to list secrets in restricted paths by exploiting a trailing-slash evaluation flaw in OpenBao.

- **Severity:** Medium 6.0 (`CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA: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:** 23 Sep 2026
- **Updated:** 24 Sep 2026
- **Also known as:** BIT-openbao-2026-63131, GHSA-xp3c-3jw3-4vcr, GO-2026-6579, MINI-4pp6-rmp3-w8pr, MINI-x2pg-37p3-6728

## What is CVE-2026-63131?

CVE-2026-63131 is a medium-severity missing authorization vulnerability in openbao, published on 23 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

OpenBao is an open source identity-based secrets management system. Prior to 2.6.0, OpenBao's vault/policy/acl.go could evaluate a broader wildcard ACL grant before more-specific trailing-wildcard ACL paths with capabilities = ["deny"] for a LIST operation. When a parent path permitted LIST and a child path was denied, the trailing-slash lookup could therefore allow listing the denied path. Other operation types are outside the repository advisory's affected scope. This issue is fixed in version 2.6.0.

Weakness: CWE-863 (Incorrect Authorization)

## Which versions are affected by CVE-2026-63131?

6 open source packages ship an affected version, including github.com/openbao/openbao and openbao.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `github.com/openbao/openbao` | Go | All versions | 0.0.0-20260713133043-f58d848c139e |
| `github.com/openbao/openbao` | Go | All versions | 0.0.0-20260713133043-f58d848c139e |
| `github.com/openbao/openbao` | Go | All versions | 0.0.0-20260713133043-f58d848c139e |
| `github.com/openbao/openbao` | Go | From 0.1.0 to 1.1.5 | None |
| `github.com/openbao/openbao` | Go | From 0.1.0 to 1.1.5 | None |
| `openbao` | Bitnami | All versions | 2.6.0 |

## How do I fix CVE-2026-63131?

Upgrade github.com/openbao/openbao to 0.0.0-20260713133043-f58d848c139e or later.

## Is CVE-2026-63131 being exploited?

There is no known exploitation of CVE-2026-63131 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-63131 and fix it if it is affected.

What it is: CVE-2026-63131 is a medium-severity missing authorization vulnerability in openbao, published on 23 Sep 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-2026-63131 in the wild and no public exploit code.

Affected packages and fixed versions:
- github.com/openbao/openbao (Go): affected all versions; fixed in 0.0.0-20260713133043-f58d848c139e
- github.com/openbao/openbao (Go): affected all versions; fixed in 0.0.0-20260713133043-f58d848c139e
- github.com/openbao/openbao (Go): affected all versions; fixed in 0.0.0-20260713133043-f58d848c139e
- github.com/openbao/openbao (Go): affected from 0.1.0 up to 1.1.5; no fix listed
- github.com/openbao/openbao (Go): affected from 0.1.0 up to 1.1.5; no fix listed
- openbao (Bitnami): affected all versions; fixed in 2.6.0

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-2026-63131/ (Markdown: https://insights.sbomify.com/CVE-2026-63131/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-63131
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-63131
- OSV: https://osv.dev/vulnerability/CVE-2026-63131

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-63131/
Summaries are generated and may contain mistakes; the official description above is the record.