# CVE-2026-35585: File Browser OS command injection in hook system

Source: https://junglewise.ai/threats/cve-2026-35585-file-browser-os-command-injection-in-hook-system  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-04-07. Updated: 2026-06-09  
License: CC BY 4.0 with a link back

CVE-2026-35585 · Severity: high · CVSS 7.2 · Published 2026-04-07

File Browser, a web-based file management interface, contains a vulnerability in its "hooks" system which allows users to run automated commands when files are uploaded or renamed. An attacker with permissions to upload or rename files can use specially crafted filenames to trick the server into executing unauthorized system commands. This could allow an attacker to take full control of the server, potentially leading to data theft or service disruption.

Technologies: [File Browser](https://junglewise.ai/threats/technologies/file-browser), [Filebrowser](https://junglewise.ai/threats/technologies/filebrowser), [github.com/filebrowser/filebrowser (Go)](https://junglewise.ai/threats/technologies/github-com-filebrowser-filebrowser), [github.com/filebrowser/filebrowser/v2 (Go)](https://junglewise.ai/threats/technologies/github-com-filebrowser-filebrowser-v2). Vendors: [File Browser](https://junglewise.ai/threats/vendors/file-browser), [FileBrowser](https://junglewise.ai/threats/vendors/filebrowser), [Go](https://junglewise.ai/threats/vendors/go).

## Quick answers

**Is CVE-2026-35585 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-35585 being exploited in the wild.

**How severe is CVE-2026-35585?** High severity, with a CVSS score of 7.2, published 7 April 2026.

**Which products and versions are affected?** File Browser < 2.33.8, 2.0.0 to 2.33.7; github.com/filebrowser/filebrowser (Go) SEMVER:introduced=0; github.com/filebrowser/filebrowser/v2 (Go) < 2.33.8, SEMVER:introduced=0,fixed=2.33.8.

**Is there a fix for CVE-2026-35585?** Yes. github.com/filebrowser/filebrowser/v2 (Go): upgrade to 2.33.8 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-35585 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2026-35585?** Check whether you run File Browser, Filebrowser, github.com/filebrowser/filebrowser (Go) or one of the others listed at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- github.com/filebrowser/filebrowser/v2 (Go): upgrade to 2.33.8 or later

  ```sh
  go get github.com/filebrowser/filebrowser/v2@v2.33.8
  ```


## Technical details

The vulnerability exists in the hook system of File Browser (versions 2.0.0 through 2.33.7), specifically within the `Runner.exec` function in `runner/runner.go`. The application uses `os.Expand` to perform variable substitution for template strings like `$FILE` and `$USERNAME` without proper sanitization or escaping. An authenticated attacker with file write, upload, or rename permissions can craft a filename containing shell metacharacters (e.g., `; id #`). When a hook event (such as `after_upload`) triggers, the unsanitized filename is injected into a shell command string, leading to arbitrary Remote Code Execution (RCE). Starting with version 2.33.8, the command execution feature is disabled by default to mitigate this risk.

## Affected products

- File Browser File Browser 2.0.0 to 2.33.7

## Identifiers

- CVE-2026-35585
- GHSA-jvpw-637p-h3pw
- GO-2026-5481

## Timeline

- 2025-06-25: other: Issue opened regarding faulty command execution features
- 2026-04-04: advisory: GitHub Security Advisory published
- 2026-04-07: disclosed: CVE published to NVD

## References

- [https://github.com/filebrowser/filebrowser/issues/5199](https://github.com/filebrowser/filebrowser/issues/5199)
- [https://github.com/filebrowser/filebrowser/security/advisories/GHSA-jvpw-637p-h3pw](https://github.com/filebrowser/filebrowser/security/advisories/GHSA-jvpw-637p-h3pw)

## Related threats

- [File Browser symlink alias path traversal bypass](https://junglewise.ai/threats/cve-2026-90930-file-browser-symlink-alias-path-traversal-bypass)
- [File Browser authorization bypass in direct-upload endpoint](https://junglewise.ai/threats/cve-2026-90929-file-browser-authorization-bypass-in-direct-upload-endpoint)
- [File Browser subtitle conversion memory exhaustion](https://junglewise.ai/threats/cve-2026-90928-file-browser-subtitle-conversion-memory-exhaustion)
- [filebrowser WebSocket message denial of service in /api/command](https://junglewise.ai/threats/cve-2026-90927-filebrowser-websocket-message-denial-of-service-in-api-command)
- [filebrowser race condition in TUS upload handler](https://junglewise.ai/threats/cve-2026-82238-filebrowser-race-condition-in-tus-upload-handler)