CVE-2026-54910: gtsteffaniak FileBrowser Quantum path traversal in subtitlesHandler

CVE-2026-54910 · Severity: high · CVSS 7.7 · Published 2026-07-20

FileBrowser Quantum is a self-hosted web application used for managing files remotely. A security flaw in how the application handles subtitle files allows any logged-in user to bypass folder restrictions and read sensitive files on the host server. This could lead to the exposure of system passwords, SSH keys, and database credentials, potentially allowing an attacker to take full control of the server.

Technologies: github.com/gtsteffaniak/filebrowser/backend (Go), Gtsteffaniak FileBrowser Quantum. Vendors: Go, Gtsteffaniak.

Quick answers

Is CVE-2026-54910 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-54910 being exploited in the wild.
How severe is CVE-2026-54910?
High severity, with a CVSS score of 7.7, published 20 July 2026.
Which products and versions are affected?
github.com/gtsteffaniak/filebrowser/backend (Go) SEMVER:introduced=0,fixed=0.0.0-20260608182036-f3f4bbe80cb5; Gtsteffaniak FileBrowser Quantum < 1.4.3-beta.
Is there a fix for CVE-2026-54910?
Yes. github.com/gtsteffaniak/filebrowser/backend (Go): upgrade to 0.0.0-20260608182036-f3f4bbe80cb5 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-54910 attacked?
It is attacked over the network, in a network appliance.
Am I affected by CVE-2026-54910?
Check whether you run github.com/gtsteffaniak/filebrowser/backend (Go) or Gtsteffaniak FileBrowser Quantum 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/gtsteffaniak/filebrowser/backend (Go): upgrade to 0.0.0-20260608182036-f3f4bbe80cb5 or later
    go get github.com/gtsteffaniak/filebrowser/backend@v0.0.0-20260608182036-f3f4bbe80cb5

Technical details

A path traversal vulnerability exists in the `subtitlesHandler` endpoint (`GET /api/media/subtitles`) of FileBrowser Quantum. The endpoint processes two query parameters, `path` and `name`, without proper sanitization. The `path` parameter is passed directly to `idx.GetRealPath()` without the standard `SanitizeUserPath()` check, allowing an attacker to escape the storage root. The `name` parameter is joined using `filepath.Join()` without stripping directory components, providing a second traversal vector. An authenticated attacker, regardless of their specific permissions or scope restrictions, can exploit these vectors to read any UTF-8 encoded file under 50MB that the server process has permission to access, such as `/etc/passwd` or JWT signing keys. The issue is fixed in version 1.4.3-beta.

Affected products

  • gtsteffaniak FileBrowser Quantum < 1.4.3-beta

Identifiers

  • CVE-2026-54910
  • GHSA-vvp7-h4fj-m28w
  • GO-2026-6164

Timeline

  • 2026-06-08: patched: Fix committed to repository
  • 2026-06-10: advisory: GitHub Security Advisory published
  • 2026-07-20: disclosed: CVE published to NVD

References

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