# CVE-2026-35605: File Browser has an access rule bypass via HasPrefix without trailing separator in path matching

> Attackers can bypass access rules to read or modify files in unintended directories due to improper path prefix matching in File Browser.

- **Severity:** Medium 6.3 (`CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 7 Apr 2026
- **Updated:** 9 Apr 2026
- **Also known as:** GHSA-5q48-q4fm-g3m6, GO-2026-5150

## What is CVE-2026-35605?

CVE-2026-35605 is a medium-severity path traversal vulnerability in filebrowser, published on 7 Apr 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 2.63.1, the Matches() function in rules/rules.go uses strings.HasPrefix() without a trailing directory separator when matching paths against access rules. A rule for /uploads also matches /uploads_backup/, granting or denying access to unintended directories.  This vulnerability is fixed in 2.63.1.

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

## Which versions are affected by CVE-2026-35605?

4 open source packages ship an affected version, including github.com/filebrowser/filebrowser/v2 and github.com/filebrowser/filebrowser. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `github.com/filebrowser/filebrowser/v2` | Go | All versions | 2.63.1 |
| `github.com/filebrowser/filebrowser/v2` | Go | All versions | 2.63.1 |
| `github.com/filebrowser/filebrowser/v2` | Go | All versions | 2.63.1 |
| `github.com/filebrowser/filebrowser` | Go | All versions | None |

Products: Filebrowser Filebrowser.

## How do I fix CVE-2026-35605?

Upgrade github.com/filebrowser/filebrowser/v2 to 2.63.1 or later.

## Is CVE-2026-35605 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-35605 exists.

## Other vulnerabilities in filebrowser

- [CVE-2026-32760](https://insights.sbomify.com/CVE-2026-32760/): File Browser Self Registration Grants Any User Admin Access When Default Permissions Include Admin (critical 10.0)
- [CVE-2026-29188](https://insights.sbomify.com/CVE-2026-29188/): File Browser: TUS Delete Endpoint Bypasses Delete Permission Check (critical 9.1)
- [CVE-2023-39612](https://insights.sbomify.com/CVE-2023-39612/): Cross-site scripting in n/a (critical 9.0)
- [CVE-2026-30934](https://insights.sbomify.com/CVE-2026-30934/): FileBrowser Quantum: Stored XSS in public share page via unsanitized share metadata (text/template misuse) (high 8.9)
- [CVE-2021-46398](https://insights.sbomify.com/CVE-2021-46398/): Cross-Site Request Forgery in Filebrowser (high 8.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-35605 and fix it if it is affected.

What it is: CVE-2026-35605 is a medium-severity path traversal vulnerability in filebrowser, published on 7 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-35605 exists.

Affected packages and fixed versions:
- github.com/filebrowser/filebrowser/v2 (Go): affected all versions; fixed in 2.63.1
- github.com/filebrowser/filebrowser/v2 (Go): affected all versions; fixed in 2.63.1
- github.com/filebrowser/filebrowser/v2 (Go): affected all versions; fixed in 2.63.1
- 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-2026-35605/ (Markdown: https://insights.sbomify.com/CVE-2026-35605/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-35605
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-35605
- OSV: https://osv.dev/vulnerability/CVE-2026-35605

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-35605/
Summaries are generated and may contain mistakes; the official description above is the record.