# CVE-2026-54091: File Browser: Incorrect access control in public directory shares via rule path rebasing

> An attacker can access blocked files in public directory shares due to incorrect path rebasing in access control rules, leading to information disclosure.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 25 Jun 2026
- **Updated:** 26 Jun 2026
- **Also known as:** GHSA-j9jx-hp4c-ghhh, GO-2026-5458

## What is CVE-2026-54091?

CVE-2026-54091 is a high-severity missing authorization vulnerability in filebrowser, published on 25 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

File Browser is a file managing interface for uploading, deleting, previewing, renaming, and editing files within a specified directory. Prior to 2.63.6, File Browser's public share handlers rebase the share owner's filesystem root to the shared directory and then evaluate descendant paths against the owner's global and per-user rules using the rebased relative path instead of the original path relative to the owner's scope. As a result, an attacker who knows a public directory share URL can access files and subdirectories that the owner explicitly blocked with rules, as long as those blocked paths are located underneath the shared directory. In the simplest case this is an unauthenticated information disclosure through `GET /api/public/share/*` and `GET /api/public/dl/*`. This vulnerability is fixed in 2.63.6.

Weakness: CWE-863 (Incorrect Authorization)

## Which versions are affected by CVE-2026-54091?

4 open source packages ship an affected version, including github.com/filebrowser/filebrowser/v2 and github.com/filebrowser/filebrowser.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `github.com/filebrowser/filebrowser/v2` | Go | All versions | 2.63.6 |
| `github.com/filebrowser/filebrowser/v2` | Go | All versions | 2.63.6 |
| `github.com/filebrowser/filebrowser/v2` | Go | All versions | 2.63.6 |
| `github.com/filebrowser/filebrowser` | Go | All versions | None |

## How do I fix CVE-2026-54091?

Upgrade github.com/filebrowser/filebrowser/v2 to 2.63.6 or later.

## Is CVE-2026-54091 being exploited?

There is no known exploitation of CVE-2026-54091 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-54091 and fix it if it is affected.

What it is: CVE-2026-54091 is a high-severity missing authorization vulnerability in filebrowser, published on 25 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-54091 in the wild and no public exploit code.

Affected packages and fixed versions:
- github.com/filebrowser/filebrowser/v2 (Go): affected all versions; fixed in 2.63.6
- github.com/filebrowser/filebrowser/v2 (Go): affected all versions; fixed in 2.63.6
- github.com/filebrowser/filebrowser/v2 (Go): affected all versions; fixed in 2.63.6
- github.com/filebrowser/filebrowser (Go): affected all versions; no fix listed

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-2026-54091/ (Markdown: https://insights.sbomify.com/CVE-2026-54091/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-54091
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-54091
- OSV: https://osv.dev/vulnerability/CVE-2026-54091

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-54091/
Summaries are generated and may contain mistakes; the official description above is the record.